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# This file is part of Autoconf. -*- Autoconf -*- # Programming languages support. # Copyright (C) 2001-2017, 2020-2021 Free Software Foundation, Inc. # This file is part of Autoconf. This program is free # software; you can redistribute it and/or modify it under the # terms of the GNU General Public License as published by the # Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # Under Section 7 of GPL version 3, you are granted additional # permissions described in the Autoconf Configure Script Exception, # version 3.0, as published by the Free Software Foundation. # # You should have received a copy of the GNU General Public License # and a copy of the Autoconf Configure Script Exception along with # this program; see the files COPYINGv3 and COPYING.EXCEPTION # respectively. If not, see <https://www.gnu.org/licenses/>. # Written by David MacKenzie, with help from # Akim Demaille, Paul Eggert, # Franc,ois Pinard, Karl Berry, Richard Pixley, Ian Lance Taylor, # Roland McGrath, Noah Friedman, david d zuhn, and many others. # Table of Contents: # # 1. Language selection # 2. and routines to produce programs in a given language. # 1a. C 2a. C # 1b. C++ # 1c. Objective C # 1d. Objective C++ # # 3. Looking for a compiler # And possibly the associated preprocessor. # 3a. C 3b. C++ 3c. Objective C 3d. Objective C++ # # 4. Compilers' characteristics. # 4a. C ## ----------------------- ## ## 1a/2a. The C language. ## ## ----------------------- ## # ------------------------ # # 1a. Language selection. # # ------------------------ # # AC_LANG(C) # ---------- # CFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options. AC_LANG_DEFINE([C], [c], [C], [CC], [], [ac_ext=c ac_cpp='$CPP $CPPFLAGS' ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&AS_MESSAGE_LOG_FD' ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&AS_MESSAGE_LOG_FD' ac_compiler_gnu=$ac_cv_c_compiler_gnu ]) # AC_LANG_C # --------- AU_DEFUN([AC_LANG_C], [AC_LANG(C)]) # ------------------------ # # 2a. Producing programs. # # ------------------------ # # AC_LANG_CONFTEST(C)(BODY) # ------------------------- # We can't use '#line $LINENO "configure"' here, since # Sun c89 (Sun WorkShop 6 update 2 C 5.3 Patch 111679-08 2002/05/09) # rejects $LINENO greater than 32767, and some configure scripts # are longer than 32767 lines. m4_define([AC_LANG_CONFTEST(C)], [cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ $1 _ACEOF]) # AC_LANG_PROGRAM(C)([PROLOGUE], [BODY]) # -------------------------------------- m4_define([AC_LANG_PROGRAM(C)], [$1 m4_ifdef([_AC_LANG_PROGRAM_C_F77_HOOKS], [_AC_LANG_PROGRAM_C_F77_HOOKS])[]dnl m4_ifdef([_AC_LANG_PROGRAM_C_FC_HOOKS], [_AC_LANG_PROGRAM_C_FC_HOOKS])[]dnl int main (void) { dnl Do *not* indent the following line: there may be CPP directives. dnl Don't move the `;' right after for the same reason. $2 ; return 0; }]) # _AC_LANG_IO_PROGRAM(C) # ---------------------- # Produce source that performs I/O, necessary for proper # cross-compiler detection. m4_define([_AC_LANG_IO_PROGRAM(C)], [AC_LANG_PROGRAM([@%:@include <stdio.h>], [FILE *f = fopen ("conftest.out", "w"); return ferror (f) || fclose (f) != 0; ])]) # AC_LANG_CALL(C)(PROLOGUE, FUNCTION) # ----------------------------------- # Avoid conflicting decl of main. m4_define([AC_LANG_CALL(C)], [AC_LANG_PROGRAM([$1 m4_if([$2], [main], , [/* Override any GCC internal prototype to avoid an error. Use char because int might match the return type of a GCC builtin and then its argument prototype would still apply. */ char $2 ();])], [return $2 ();])]) # AC_LANG_FUNC_LINK_TRY(C)(FUNCTION) # ---------------------------------- # Don't include <ctype.h> because on OSF/1 3.0 it includes # <sys/types.h> which includes <sys/select.h> which contains a # prototype for select. Similarly for bzero. # # This test used to merely assign f=$1 in main(), but that was # optimized away by HP unbundled cc A.05.36 for ia64 under +O3, # presumably on the basis that there's no need to do that store if the # program is about to exit. Conversely, the AIX linker optimizes an # unused external declaration that initializes f=$1. So this test # program has both an external initialization of f, and a use of f in # main that affects the exit status. # m4_define([AC_LANG_FUNC_LINK_TRY(C)], [AC_LANG_PROGRAM( [/* Define $1 to an innocuous variant, in case <limits.h> declares $1. 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The C++ language. ## ## ---------------------- ## # AC_LANG(C++) # ------------ # CXXFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options. AC_LANG_DEFINE([C++], [cxx], [CXX], [CXX], [C], [ac_ext=cpp ac_cpp='$CXXCPP $CPPFLAGS' ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&AS_MESSAGE_LOG_FD' ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&AS_MESSAGE_LOG_FD' ac_compiler_gnu=$ac_cv_cxx_compiler_gnu ]) # AC_LANG_CALL(C++)(PROLOGUE, FUNCTION) # ------------------------------------- m4_define([AC_LANG_CALL(C++)], dnl We do not know the function signature of the real $2. dnl Declare it in a namespace so the compiler doesn't recognize it dnl (with, most likely, a clashing prototype); the 'extern "C"' hides dnl the namespace from the linker. dnl Use 'int' for the return type, because some C++ compilers consider dnl 'namespace conftest { extern "C" void main (); }' to be an dnl erroneous redeclaration of ::main, namespace notwithstanding. dnl The logic they're applying could be extended in the future to dnl other built-in extern "C" functions, but let's worry about that dnl when it actually happens. [AC_LANG_PROGRAM([[$1 namespace conftest { extern "C" int $2 (); }]], [[return conftest::$2 ();]])]) # AC_LANG_CPLUSPLUS # ----------------- AU_DEFUN([AC_LANG_CPLUSPLUS], [AC_LANG(C++)]) ## ------------------------------ ## ## 1c. The Objective C language. ## ## ------------------------------ ## # AC_LANG(Objective C) # -------------------- AC_LANG_DEFINE([Objective C], [objc], [OBJC], [OBJC], [C], [ac_ext=m ac_cpp='$OBJCPP $CPPFLAGS' ac_compile='$OBJC -c $OBJCFLAGS $CPPFLAGS conftest.$ac_ext >&AS_MESSAGE_LOG_FD' ac_link='$OBJC -o conftest$ac_exeext $OBJCFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&AS_MESSAGE_LOG_FD' ac_compiler_gnu=$ac_cv_objc_compiler_gnu ]) # AC_LANG_OBJC # ------------ AU_DEFUN([AC_LANG_OBJC], [AC_LANG(Objective C)]) ## -------------------------------- ## ## 1d. 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AC_DEFUN([_AC_ARG_VAR_CPPFLAGS], [AC_ARG_VAR([CPPFLAGS], [(Objective) C/C++ preprocessor flags, e.g. -I<include dir> if you have headers in a nonstandard directory <include dir>])]) # _AC_ARG_VAR_LDFLAGS # ------------------- # Document and register LDFLAGS, which is used by # AC_PROG_{CC, CXX, F77, FC, OBJC, OBJCXX}. AC_DEFUN([_AC_ARG_VAR_LDFLAGS], [AC_ARG_VAR([LDFLAGS], [linker flags, e.g. -L<lib dir> if you have libraries in a nonstandard directory <lib dir>])]) # _AC_ARG_VAR_LIBS # ---------------- # Document and register LIBS, which is used by # AC_PROG_{CC, CXX, F77, FC, OBJC, OBJCXX}. AC_DEFUN([_AC_ARG_VAR_LIBS], [AC_ARG_VAR([LIBS], [libraries to pass to the linker, e.g. -l<library>])]) # AC_LANG_PREPROC(C) # ------------------ # Find the C preprocessor. Must be AC_DEFUN'd to be AC_REQUIRE'able. 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AU_DEFUN([ac_cv_prog_gxx], [ac_cv_cxx_compiler_gnu]) # AC_PROG_CXX([LIST-OF-COMPILERS]) # -------------------------------- # LIST-OF-COMPILERS is a space separated list of C++ compilers to search # for (if not specified, a default list is used). This just gives the # user an opportunity to specify an alternative search list for the C++ # compiler. # aCC HP-UX C++ compiler much better than `CC', so test before. # FCC Fujitsu C++ compiler # KCC KAI C++ compiler # RCC Rational C++ # xlC_r IBM XL C++ for AIX (with support for reentrant code) # xlC IBM XL C++ for AIX AN_MAKEVAR([CXX], [AC_PROG_CXX]) AN_PROGRAM([CC], [AC_PROG_CXX]) AN_PROGRAM([c++], [AC_PROG_CXX]) AN_PROGRAM([g++], [AC_PROG_CXX]) AC_DEFUN([AC_PROG_CXX], [AC_LANG_PUSH(C++)dnl AC_ARG_VAR([CXX], [C++ compiler command])dnl AC_ARG_VAR([CXXFLAGS], [C++ compiler flags])dnl _AC_ARG_VAR_LDFLAGS()dnl _AC_ARG_VAR_LIBS()dnl _AC_ARG_VAR_CPPFLAGS()dnl _AC_ARG_VAR_PRECIOUS([CCC])dnl if test -z "$CXX"; then if test -n "$CCC"; then CXX=$CCC else AC_CHECK_TOOLS(CXX, [m4_default([$1], [g++ c++ gpp aCC CC cxx cc++ cl.exe FCC KCC RCC xlC_r xlC clang++])], g++) fi fi # Provide some information about the compiler. _AS_ECHO_LOG([checking for _AC_LANG compiler version]) set X $ac_compile ac_compiler=$[2] for ac_option in --version -v -V -qversion; do _AC_DO_LIMIT([$ac_compiler $ac_option >&AS_MESSAGE_LOG_FD]) done m4_expand_once([_AC_COMPILER_EXEEXT])[]dnl m4_expand_once([_AC_COMPILER_OBJEXT])[]dnl _AC_LANG_COMPILER_GNU if test $ac_compiler_gnu = yes; then GXX=yes else GXX= fi _AC_PROG_CXX_G _AC_PROG_CXX_STDCXX_EDITION AC_LANG_POP(C++)dnl ])# AC_PROG_CXX # _AC_PROG_CXX_G # -------------- # Check whether -g works, even if CXXFLAGS is set, in case the package # plays around with CXXFLAGS (such as to build both debugging and # normal versions of a library), tasteless as that idea is. # Don't consider -g to work if it generates warnings when plain compiles don't. m4_define([_AC_PROG_CXX_G], [ac_test_CXXFLAGS=${CXXFLAGS+y} ac_save_CXXFLAGS=$CXXFLAGS AC_CACHE_CHECK(whether $CXX accepts -g, ac_cv_prog_cxx_g, [ac_save_cxx_werror_flag=$ac_cxx_werror_flag ac_cxx_werror_flag=yes ac_cv_prog_cxx_g=no CXXFLAGS="-g" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [ac_cv_prog_cxx_g=yes], [CXXFLAGS="" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [], [ac_cxx_werror_flag=$ac_save_cxx_werror_flag CXXFLAGS="-g" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [ac_cv_prog_cxx_g=yes])])]) ac_cxx_werror_flag=$ac_save_cxx_werror_flag]) if test $ac_test_CXXFLAGS; then CXXFLAGS=$ac_save_CXXFLAGS elif test $ac_cv_prog_cxx_g = yes; then if test "$GXX" = yes; then CXXFLAGS="-g -O2" else CXXFLAGS="-g" fi else if test "$GXX" = yes; then CXXFLAGS="-O2" else CXXFLAGS= fi fi[]dnl ])# _AC_PROG_CXX_G # AC_PROG_CXX_C_O # --------------- # Test if the C++ compiler accepts the options `-c' and `-o' # simultaneously, and define `CXX_NO_MINUS_C_MINUS_O' if it does not. AC_DEFUN([AC_PROG_CXX_C_O], [AC_REQUIRE([AC_PROG_CXX])dnl AC_LANG_PUSH([C++])dnl AC_CACHE_CHECK([whether $CXX understands -c and -o together], [ac_cv_prog_cxx_c_o], [AC_LANG_CONFTEST([AC_LANG_PROGRAM([])]) # We test twice because some compilers refuse to overwrite an existing # `.o' file with `-o', although they will create one. ac_try='$CXX $CXXFLAGS -c conftest.$ac_ext -o conftest2.$ac_objext >&AS_MESSAGE_LOG_FD' rm -f conftest2.* if _AC_DO_VAR(ac_try) && test -f conftest2.$ac_objext && _AC_DO_VAR(ac_try); then ac_cv_prog_cxx_c_o=yes else ac_cv_prog_cxx_c_o=no fi rm -rf conftest*]) if test $ac_cv_prog_cxx_c_o = no; then AC_DEFINE(CXX_NO_MINUS_C_MINUS_O, 1, [Define to 1 if your C++ compiler doesn't accept -c and -o together.]) fi AC_LANG_POP([C++])dnl ])# AC_PROG_CXX_C_O # ------------------------------ # # 3c. The Objective C compiler. # # ------------------------------ # # AC_LANG_PREPROC(Objective C) # ---------------------------- # Find the Objective C preprocessor. Must be AC_DEFUN'd to be AC_REQUIRE'able. AC_DEFUN([AC_LANG_PREPROC(Objective C)], [AC_REQUIRE([AC_PROG_OBJCPP])]) # AC_PROG_OBJCPP # -------------- # Find a working Objective C preprocessor. AC_DEFUN([AC_PROG_OBJCPP], [AC_REQUIRE([AC_PROG_OBJC])dnl AC_ARG_VAR([OBJCPP], [Objective C preprocessor])dnl _AC_ARG_VAR_CPPFLAGS()dnl AC_LANG_PUSH(Objective C)dnl AC_MSG_CHECKING([how to run the Objective C preprocessor]) if test -z "$OBJCPP"; then AC_CACHE_VAL(ac_cv_prog_OBJCPP, [dnl # Double quotes because $OBJC needs to be expanded for OBJCPP in "$OBJC -E" cpp /lib/cpp do _AC_PROG_PREPROC_WORKS_IFELSE([break]) done ac_cv_prog_OBJCPP=$OBJCPP ])dnl OBJCPP=$ac_cv_prog_OBJCPP else ac_cv_prog_OBJCPP=$OBJCPP fi AC_MSG_RESULT([$OBJCPP]) _AC_PROG_PREPROC_WORKS_IFELSE([], [AC_MSG_FAILURE([Objective C preprocessor "$OBJCPP" fails sanity check])]) AC_SUBST(OBJCPP)dnl AC_LANG_POP(Objective C)dnl ])# AC_PROG_OBJCPP # AC_LANG_COMPILER(Objective C) # ----------------------------- # Find the Objective C compiler. Must be AC_DEFUN'd to be AC_REQUIRE'able. AC_DEFUN([AC_LANG_COMPILER(Objective C)], [AC_REQUIRE([AC_PROG_OBJC])]) # AC_PROG_OBJC([LIST-OF-COMPILERS]) # --------------------------------- # LIST-OF-COMPILERS is a space separated list of Objective C compilers to # search for (if not specified, a default list is used). This just gives # the user an opportunity to specify an alternative search list for the # Objective C compiler. # objcc StepStone Objective-C compiler (also "standard" name for OBJC) # objc David Stes' POC. If you installed this, you likely want it. # cc Native C compiler (for instance, Apple). # CC You never know. AN_MAKEVAR([OBJC], [AC_PROG_OBJC]) AN_PROGRAM([objcc], [AC_PROG_OBJC]) AN_PROGRAM([objc], [AC_PROG_OBJC]) AC_DEFUN([AC_PROG_OBJC], [AC_LANG_PUSH(Objective C)dnl AC_ARG_VAR([OBJC], [Objective C compiler command])dnl AC_ARG_VAR([OBJCFLAGS], [Objective C compiler flags])dnl _AC_ARG_VAR_LDFLAGS()dnl _AC_ARG_VAR_LIBS()dnl _AC_ARG_VAR_CPPFLAGS()dnl _AC_ARG_VAR_PRECIOUS([OBJC])dnl AC_CHECK_TOOLS(OBJC, [m4_default([$1], [gcc objcc objc cc CC clang])], gcc) # Provide some information about the compiler. _AS_ECHO_LOG([checking for _AC_LANG compiler version]) set X $ac_compile ac_compiler=$[2] for ac_option in --version -v -V -qversion; do _AC_DO_LIMIT([$ac_compiler $ac_option >&AS_MESSAGE_LOG_FD]) done m4_expand_once([_AC_COMPILER_EXEEXT])[]dnl m4_expand_once([_AC_COMPILER_OBJEXT])[]dnl _AC_LANG_COMPILER_GNU if test $ac_compiler_gnu = yes; then GOBJC=yes else GOBJC= fi _AC_PROG_OBJC_G AC_LANG_POP(Objective C)dnl ])# AC_PROG_OBJC # _AC_PROG_OBJC_G # --------------- # Check whether -g works, even if OBJCFLAGS is set, in case the package # plays around with OBJCFLAGS (such as to build both debugging and # normal versions of a library), tasteless as that idea is. # Don't consider -g to work if it generates warnings when plain compiles don't. m4_define([_AC_PROG_OBJC_G], [ac_test_OBJCFLAGS=${OBJCFLAGS+y} ac_save_OBJCFLAGS=$OBJCFLAGS AC_CACHE_CHECK(whether $OBJC accepts -g, ac_cv_prog_objc_g, [ac_save_objc_werror_flag=$ac_objc_werror_flag ac_objc_werror_flag=yes ac_cv_prog_objc_g=no OBJCFLAGS="-g" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [ac_cv_prog_objc_g=yes], [OBJCFLAGS="" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [], [ac_objc_werror_flag=$ac_save_objc_werror_flag OBJCFLAGS="-g" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [ac_cv_prog_objc_g=yes])])]) ac_objc_werror_flag=$ac_save_objc_werror_flag]) if test $ac_test_OBJCFLAGS; then OBJCFLAGS=$ac_save_OBJCFLAGS elif test $ac_cv_prog_objc_g = yes; then if test "$GOBJC" = yes; then OBJCFLAGS="-g -O2" else OBJCFLAGS="-g" fi else if test "$GOBJC" = yes; then OBJCFLAGS="-O2" else OBJCFLAGS= fi fi[]dnl ])# _AC_PROG_OBJC_G # -------------------------------- # # 3d. The Objective C++ compiler. # # -------------------------------- # # AC_LANG_PREPROC(Objective C++) # ------------------------------ # Find the Objective C++ preprocessor. Must be AC_DEFUN'd to be AC_REQUIRE'able. AC_DEFUN([AC_LANG_PREPROC(Objective C++)], [AC_REQUIRE([AC_PROG_OBJCXXCPP])]) # AC_PROG_OBJCXXCPP # ----------------- # Find a working Objective C++ preprocessor. AC_DEFUN([AC_PROG_OBJCXXCPP], [AC_REQUIRE([AC_PROG_OBJCXX])dnl AC_ARG_VAR([OBJCXXCPP], [Objective C++ preprocessor])dnl _AC_ARG_VAR_CPPFLAGS()dnl AC_LANG_PUSH(Objective C++)dnl AC_MSG_CHECKING([how to run the Objective C++ preprocessor]) if test -z "$OBJCXXCPP"; then AC_CACHE_VAL(ac_cv_prog_OBJCXXCPP, [dnl # Double quotes because $OBJCXX needs to be expanded for OBJCXXCPP in "$OBJCXX -E" cpp /lib/cpp do _AC_PROG_PREPROC_WORKS_IFELSE([break]) done ac_cv_prog_OBJCXXCPP=$OBJCXXCPP ])dnl OBJCXXCPP=$ac_cv_prog_OBJCXXCPP else ac_cv_prog_OBJCXXCPP=$OBJCXXCPP fi AC_MSG_RESULT([$OBJCXXCPP]) _AC_PROG_PREPROC_WORKS_IFELSE([], [AC_MSG_FAILURE([Objective C++ preprocessor "$OBJCXXCPP" fails sanity check])]) AC_SUBST(OBJCXXCPP)dnl AC_LANG_POP(Objective C++)dnl ])# AC_PROG_OBJCXXCPP # AC_LANG_COMPILER(Objective C++) # ------------------------------- # Find the Objective C++ compiler. Must be AC_DEFUN'd to be AC_REQUIRE'able. AC_DEFUN([AC_LANG_COMPILER(Objective C++)], [AC_REQUIRE([AC_PROG_OBJCXX])]) # AC_PROG_OBJCXX([LIST-OF-COMPILERS]) # ----------------------------------- # LIST-OF-COMPILERS is a space separated list of Objective C++ compilers to # search for (if not specified, a default list is used). This just gives # the user an opportunity to specify an alternative search list for the # Objective C++ compiler. # FIXME: this list is pure guesswork # objc++ StepStone Objective-C++ compiler (also "standard" name for OBJCXX) # objcxx David Stes' POC. If you installed this, you likely want it. # c++ Native C++ compiler (for instance, Apple). # CXX You never know. AN_MAKEVAR([OBJCXX], [AC_PROG_OBJCXX]) AN_PROGRAM([objcxx], [AC_PROG_OBJCXX]) AC_DEFUN([AC_PROG_OBJCXX], [AC_LANG_PUSH(Objective C++)dnl AC_ARG_VAR([OBJCXX], [Objective C++ compiler command])dnl AC_ARG_VAR([OBJCXXFLAGS], [Objective C++ compiler flags])dnl _AC_ARG_VAR_LDFLAGS()dnl _AC_ARG_VAR_LIBS()dnl _AC_ARG_VAR_CPPFLAGS()dnl _AC_ARG_VAR_PRECIOUS([OBJCXX])dnl AC_CHECK_TOOLS(OBJCXX, [m4_default([$1], [g++ objc++ objcxx c++ CXX])], g++) # Provide some information about the compiler. _AS_ECHO_LOG([checking for _AC_LANG compiler version]) set X $ac_compile ac_compiler=$[2] for ac_option in --version -v -V -qversion; do _AC_DO_LIMIT([$ac_compiler $ac_option >&AS_MESSAGE_LOG_FD]) done m4_expand_once([_AC_COMPILER_EXEEXT])[]dnl m4_expand_once([_AC_COMPILER_OBJEXT])[]dnl _AC_LANG_COMPILER_GNU if test $ac_compiler_gnu = yes; then GOBJCXX=yes else GOBJCXX= fi _AC_PROG_OBJCXX_G AC_LANG_POP(Objective C++)dnl ])# AC_PROG_OBJCXX # _AC_PROG_OBJCXX_G # ----------------- # Check whether -g works, even if OBJCFLAGS is set, in case the package # plays around with OBJCFLAGS (such as to build both debugging and # normal versions of a library), tasteless as that idea is. # Don't consider -g to work if it generates warnings when plain compiles don't. m4_define([_AC_PROG_OBJCXX_G], [ac_test_OBJCXXFLAGS=${OBJCXXFLAGS+y} ac_save_OBJCXXFLAGS=$OBJCXXFLAGS AC_CACHE_CHECK(whether $OBJCXX accepts -g, ac_cv_prog_objcxx_g, [ac_save_objcxx_werror_flag=$ac_objcxx_werror_flag ac_objcxx_werror_flag=yes ac_cv_prog_objcxx_g=no OBJCXXFLAGS="-g" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [ac_cv_prog_objcxx_g=yes], [OBJCXXFLAGS="" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [], [ac_objcxx_werror_flag=$ac_save_objcxx_werror_flag OBJCXXFLAGS="-g" _AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [ac_cv_prog_objcxx_g=yes])])]) ac_objcxx_werror_flag=$ac_save_objcx_werror_flag]) if test $ac_test_OBJCXXFLAGS; then OBJCXXFLAGS=$ac_save_OBJCXXFLAGS elif test $ac_cv_prog_objcxx_g = yes; then if test "$GOBJCXX" = yes; then OBJCXXFLAGS="-g -O2" else OBJCXXFLAGS="-g" fi else if test "$GOBJCXX" = yes; then OBJCXXFLAGS="-O2" else OBJCXXFLAGS= fi fi[]dnl ])# _AC_PROG_OBJCXX_G ## ------------------------------- ## ## 4. Compilers' characteristics. ## ## ------------------------------- ## # -------------------------------- # # 4a. C compiler characteristics. # # -------------------------------- # # Fragments of these programs are emitted as shell variables in the # INIT_PREPARE diversion, because they can get long and we want only # one copy of each fragment in the generated configure. This also # makes quoting control a bit easier. Try to avoid using ', however, # because putting single quotes into a single-quoted shell string is # awkward (you must write '\'' for each ' you want in the program). # # Warning: to avoid incorrect answers due to unused-variable warnings # and/or overly aggressive optimizers, each variable (global or not) # in these programs should be used, and each function should be # called. Unlike how AC_LANG_PROGRAM(C) usually does it, we declare # main with its usual two arguments, to give the test fragments some # convenient non-compile-time-constant values to pass around. In main, # there is an int variable 'ok' which will eventually become the return # value; use `ok |= ...' to consume the results of operations. # # Warning: each test program may only use the headers required to # exist in the relevant standard's *freestanding* environment, in case # the C compiler targets such an environment. (Therefore, almost no # features of the C89/C99/C11 standard *library* are probed. Use # AC_CHECK_HEADER, AC_CHECK_FUNC, etc. for that.) However, these # programs are only compiled and not linked, so it is ok to declare # external functions and then call them without worrying about whether # they actually exist. # # The C89 freestanding headers are: # <float.h> <limits.h> <stdarg.h> <stddef.h> # C99 adds: # <iso646.h> <stdbool.h> <stdint.h> # C11 adds: # <stdalign.h> <stdnoreturn.h> AC_DEFUN([_AC_C_C89_TEST_GLOBALS], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C89 (global declarations) ac_c_conftest_c89_globals=' /* Does the compiler advertise C89 conformance? Do not test the value of __STDC__, because some compilers set it to 0 while being otherwise adequately conformant. */ #if !defined __STDC__ # error "Compiler does not advertise C89 conformance" #endif #include <stddef.h> #include <stdarg.h> struct stat; /* Most of the following tests are stolen from RCS 5.7 src/conf.sh. */ struct buf { int x; }; struct buf * (*rcsopen) (struct buf *, struct stat *, int); static char *e (p, i) char **p; int i; { return p[i]; } static char *f (char * (*g) (char **, int), char **p, ...) { char *s; va_list v; va_start (v,p); s = g (p, va_arg (v,int)); va_end (v); return s; } /* OSF 4.0 Compaq cc is some sort of almost-ANSI by default. It has function prototypes and stuff, but not \xHH hex character constants. These do not provoke an error unfortunately, instead are silently treated as an "x". The following induces an error, until -std is added to get proper ANSI mode. Curiously \x00 != x always comes out true, for an array size at least. It is necessary to write \x00 == 0 to get something that is true only with -std. */ int osf4_cc_array ['\''\x00'\'' == 0 ? 1 : -1]; /* IBM C 6 for AIX is almost-ANSI by default, but it replaces macro parameters inside strings and character constants. */ #define FOO(x) '\''x'\'' int xlc6_cc_array[FOO(a) == '\''x'\'' ? 1 : -1]; int test (int i, double x); struct s1 {int (*f) (int a);}; struct s2 {int (*f) (double a);}; int pairnames (int, char **, int *(*)(struct buf *, struct stat *, int), int, int);' ]])]) AC_DEFUN([_AC_C_C89_TEST_MAIN], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C89 (body of main). ac_c_conftest_c89_main=' ok |= (argc == 0 || f (e, argv, 0) != argv[0] || f (e, argv, 1) != argv[1]); ' ]])]) AC_DEFUN([_AC_C_C99_TEST_GLOBALS], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C99 (global declarations) ac_c_conftest_c99_globals=' // Does the compiler advertise C99 conformance? #if !defined __STDC_VERSION__ || __STDC_VERSION__ < 199901L # error "Compiler does not advertise C99 conformance" #endif #include <stdbool.h> extern int puts (const char *); extern int printf (const char *, ...); extern int dprintf (int, const char *, ...); extern void *malloc (size_t); // Check varargs macros. These examples are taken from C99 6.10.3.5. // dprintf is used instead of fprintf to avoid needing to declare // FILE and stderr. #define debug(...) dprintf (2, __VA_ARGS__) #define showlist(...) puts (#__VA_ARGS__) #define report(test,...) ((test) ? puts (#test) : printf (__VA_ARGS__)) static void test_varargs_macros (void) { int x = 1234; int y = 5678; debug ("Flag"); debug ("X = %d\n", x); showlist (The first, second, and third items.); report (x>y, "x is %d but y is %d", x, y); } // Check long long types. #define BIG64 18446744073709551615ull #define BIG32 4294967295ul #define BIG_OK (BIG64 / BIG32 == 4294967297ull && BIG64 % BIG32 == 0) #if !BIG_OK #error "your preprocessor is broken" #endif #if BIG_OK #else #error "your preprocessor is broken" #endif static long long int bignum = -9223372036854775807LL; static unsigned long long int ubignum = BIG64; struct incomplete_array { int datasize; double data[]; }; struct named_init { int number; const wchar_t *name; double average; }; typedef const char *ccp; static inline int test_restrict (ccp restrict text) { // See if C++-style comments work. // Iterate through items via the restricted pointer. // Also check for declarations in for loops. for (unsigned int i = 0; *(text+i) != '\''\0'\''; ++i) continue; return 0; } // Check varargs and va_copy. static bool test_varargs (const char *format, ...) { va_list args; va_start (args, format); va_list args_copy; va_copy (args_copy, args); const char *str = ""; int number = 0; float fnumber = 0; while (*format) { switch (*format++) { case '\''s'\'': // string str = va_arg (args_copy, const char *); break; case '\''d'\'': // int number = va_arg (args_copy, int); break; case '\''f'\'': // float fnumber = va_arg (args_copy, double); break; default: break; } } va_end (args_copy); va_end (args); return *str && number && fnumber; } ' ]])]) AC_DEFUN([_AC_C_C99_TEST_MAIN], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C99 (body of main). ac_c_conftest_c99_main=' // Check bool. _Bool success = false; success |= (argc != 0); // Check restrict. if (test_restrict ("String literal") == 0) success = true; char *restrict newvar = "Another string"; // Check varargs. success &= test_varargs ("s, d'\'' f .", "string", 65, 34.234); test_varargs_macros (); // Check flexible array members. struct incomplete_array *ia = malloc (sizeof (struct incomplete_array) + (sizeof (double) * 10)); ia->datasize = 10; for (int i = 0; i < ia->datasize; ++i) ia->data[i] = i * 1.234; // Check named initializers. struct named_init ni = { .number = 34, .name = L"Test wide string", .average = 543.34343, }; ni.number = 58; int dynamic_array[ni.number]; dynamic_array[0] = argv[0][0]; dynamic_array[ni.number - 1] = 543; // work around unused variable warnings ok |= (!success || bignum == 0LL || ubignum == 0uLL || newvar[0] == '\''x'\'' || dynamic_array[ni.number - 1] != 543); ' ]])]) AC_DEFUN([_AC_C_C11_TEST_GLOBALS], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C11 (global declarations) ac_c_conftest_c11_globals=' // Does the compiler advertise C11 conformance? #if !defined __STDC_VERSION__ || __STDC_VERSION__ < 201112L # error "Compiler does not advertise C11 conformance" #endif // Check _Alignas. char _Alignas (double) aligned_as_double; char _Alignas (0) no_special_alignment; extern char aligned_as_int; char _Alignas (0) _Alignas (int) aligned_as_int; // Check _Alignof. enum { int_alignment = _Alignof (int), int_array_alignment = _Alignof (int[100]), char_alignment = _Alignof (char) }; _Static_assert (0 < -_Alignof (int), "_Alignof is signed"); // Check _Noreturn. int _Noreturn does_not_return (void) { for (;;) continue; } // Check _Static_assert. struct test_static_assert { int x; _Static_assert (sizeof (int) <= sizeof (long int), "_Static_assert does not work in struct"); long int y; }; // Check UTF-8 literals. #define u8 syntax error! char const utf8_literal[] = u8"happens to be ASCII" "another string"; // Check duplicate typedefs. typedef long *long_ptr; typedef long int *long_ptr; typedef long_ptr long_ptr; // Anonymous structures and unions -- taken from C11 6.7.2.1 Example 1. struct anonymous { union { struct { int i; int j; }; struct { int k; long int l; } w; }; int m; } v1; ' ]])]) AC_DEFUN([_AC_C_C11_TEST_MAIN], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C11 (body of main). ac_c_conftest_c11_main=' _Static_assert ((offsetof (struct anonymous, i) == offsetof (struct anonymous, w.k)), "Anonymous union alignment botch"); v1.i = 2; v1.w.k = 5; ok |= v1.i != 5; ' ]])]) AC_DEFUN([_AC_C_C89_TEST_PROGRAM], [AC_REQUIRE([_AC_C_C89_TEST_GLOBALS])dnl AC_REQUIRE([_AC_C_C89_TEST_MAIN])dnl m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C89 (complete). ac_c_conftest_c89_program="${ac_c_conftest_c89_globals} int main (int argc, char **argv) { int ok = 0; ${ac_c_conftest_c89_main} return ok; } " ]])]) AC_DEFUN([_AC_C_C99_TEST_PROGRAM], [AC_REQUIRE([_AC_C_C89_TEST_GLOBALS])dnl AC_REQUIRE([_AC_C_C89_TEST_MAIN])dnl AC_REQUIRE([_AC_C_C99_TEST_GLOBALS])dnl AC_REQUIRE([_AC_C_C99_TEST_MAIN])dnl m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C99 (complete). ac_c_conftest_c99_program="${ac_c_conftest_c89_globals} ${ac_c_conftest_c99_globals} int main (int argc, char **argv) { int ok = 0; ${ac_c_conftest_c89_main} ${ac_c_conftest_c99_main} return ok; } " ]])]) AC_DEFUN([_AC_C_C11_TEST_PROGRAM], [AC_REQUIRE([_AC_C_C89_TEST_GLOBALS])dnl AC_REQUIRE([_AC_C_C89_TEST_MAIN])dnl AC_REQUIRE([_AC_C_C99_TEST_GLOBALS])dnl AC_REQUIRE([_AC_C_C99_TEST_MAIN])dnl AC_REQUIRE([_AC_C_C11_TEST_GLOBALS])dnl AC_REQUIRE([_AC_C_C11_TEST_MAIN])dnl m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C11 (complete). ac_c_conftest_c11_program="${ac_c_conftest_c89_globals} ${ac_c_conftest_c99_globals} ${ac_c_conftest_c11_globals} int main (int argc, char **argv) { int ok = 0; ${ac_c_conftest_c89_main} ${ac_c_conftest_c99_main} ${ac_c_conftest_c11_main} return ok; } " ]])]) # _AC_C_C89_OPTIONS # ----------------- # Whitespace-separated list of options that might put the C compiler # into a mode conforming to ISO C1990 with extensions. Do not try # "strictly conforming" modes (e.g. gcc's -std=c90); they break some # systems' header files. If more than one option is needed, put # shell quotes around the group. # # AIX circa 2003 -qlanglvl=extc89 # old AIX -qlanglvl=ansi # Ultrix, OSF/1, Tru64 -std # HP-UX 10.20 and later -Ae # HP-UX older versions -Aa -D_HPUX_SOURCE # SVR4 -Xc -D__EXTENSIONS__ m4_define([_AC_C_C89_OPTIONS], [ -qlanglvl=extc89 -qlanglvl=ansi -std -Ae "-Aa -D_HPUX_SOURCE" "-Xc -D__EXTENSIONS__" ]) # _AC_C_C99_OPTIONS # ----------------- # Whitespace-separated list of options that might put the C compiler # into a mode conforming to ISO C1999 with extensions. Do not try # "strictly conforming" modes (e.g. gcc's -std=c99); they break some # systems' header files. If more than one option is needed, put # shell quotes around the group. # # GCC, Clang -std=gnu99 # Intel ICC -std=c99, -c99 (deprecated) # Note: because -std=c99 puts GCC in strictly conforming mode, # this option must be tested *after* -std=gnu99. # IRIX -c99 # Tru64 -c99 # IBM XL C -qlanglvl=extc1x (V12.1; does not pass C11 test) # IBM XL C -qlanglvl=extc99 (pre-V12.1) # HP cc -AC99 # Solaris -D_STDC_C99= # Note: acc's -xc99 option uses linker magic to define the external # symbol __xpg4 as if by "int __xpg4 = 1;", which enables C99 # behavior for C library functions. This is not wanted here, # because it means that a single module compiled with -xc99 alters # C runtime behavior for the entire program, not for just the # module. Instead, define the (private) symbol _STDC_C99, which # suppresses a bogus failure in <stdbool.h>. The resulting compiler # passes the test case here, and that's good enough. # For more, please see the thread starting at: # https://lists.gnu.org/archive/html/autoconf/2010-12/msg00059.html m4_define([_AC_C_C99_OPTIONS], [ -std=gnu99 -std=c99 -c99 -qlanglvl=extc1x -qlanglvl=extc99 -AC99 -D_STDC_C99= ]) # _AC_C_C11_OPTIONS # ----------------- # Whitespace-separated list of options that might put the C compiler # into a mode conforming to ISO C2011 with extensions. Do not try # "strictly conforming" modes (e.g. gcc's -std=c11); they break some # systems' header files. If more than one option is needed, put # shell quotes around the group. # # GCC, Clang -std=gnu11 # # For IBM XL C for AIX V16.1 or later, '-std=gnu11' should work if # the user configured with CC='xlclang'. Otherwise, do not try # -qlanglvl=extc1x as xlc with IBM XL C V16.1 (the latest version as # of August 2020) does not pass the C11 test. Instead, try extc1x when # compiling the C99 test instead, since it enables _Static_assert and # _Noreturn, which is a win. m4_define([_AC_C_C11_OPTIONS], [ -std=gnu11 ]) # _AC_PROG_CC_STDC_EDITION_TRY(EDITION) # ------------------------------------- # Subroutine of _AC_PROG_CC_STDC_EDITION. Not to be called directly. # # Check whether the C compiler accepts features of EDITION of the # C standard. EDITION should be a two-digit year (e.g. 89, 99, 11). # (FIXME: Switch to four-digit years for futureproofing.) # This is done by compiling the test program defined by # _AC_C_C{EDITION}_TEST_PROGRAM, first with no additional # command-line options, and then with each of the options # in the space-separated list defined by _AC_C_C{EDITION}_OPTIONS. # # If we find a way to make the test program compile, set cache variable # ac_cv_prog_cc_cEDITION to the options required (if any), and add those # options to $CC. Set shell variable ac_prog_cc_stdc to `cEDITION', # and set shell variable ac_cv_prog_cc_stdc to the options required. # (Neither of these variables is AC_SUBSTed. ac_cv_prog_cc_stdc used # to be a cache variable and is preserved with this name for backward # compatibility.) Otherwise, ac_cv_prog_cc_cEDITION is set to `no' # and the other variables are not changed. # # If ac_prog_cc_stdc is already set to a value other than `no', # the shell code produced by this macro does nothing. This is so # _AC_PROG_CC_STDC_EDITION can use m4_map to iterate through # all the editions. AC_DEFUN([_AC_PROG_CC_STDC_EDITION_TRY], [AC_LANG_ASSERT([C])]dnl [AC_REQUIRE([_AC_C_C$1_TEST_PROGRAM])]dnl [AS_IF([test x$ac_prog_cc_stdc = xno], [AC_MSG_CHECKING([for $CC option to enable C$1 features]) AC_CACHE_VAL([ac_cv_prog_cc_c$1], [ac_cv_prog_cc_c$1=no ac_save_CC=$CC AC_LANG_CONFTEST([AC_LANG_DEFINES_PROVIDED][$][ac_c_conftest_c$1_program]) for ac_arg in '' m4_normalize(m4_defn([_AC_C_C$1_OPTIONS])) do CC="$ac_save_CC $ac_arg" _AC_COMPILE_IFELSE([], [ac_cv_prog_cc_c$1=$ac_arg]) test "x$ac_cv_prog_cc_c$1" != "xno" && break done rm -f conftest.$ac_ext CC=$ac_save_CC]) AS_IF([test "x$ac_cv_prog_cc_c$1" = xno], [AC_MSG_RESULT([unsupported])], [AS_IF([test "x$ac_cv_prog_cc_c$1" = x], [AC_MSG_RESULT([none needed])], [AC_MSG_RESULT([$ac_cv_prog_cc_c$1]) CC="$CC $ac_cv_prog_cc_c$1"]) ac_cv_prog_cc_stdc=$ac_cv_prog_cc_c$1 ac_prog_cc_stdc=c$1])]) ]) # _AC_PROG_CC_STDC_EDITION # ------------------------ # Detect the most recent edition of the ISO C standard that is # supported by the C compiler. Add command-line options to $CC, if # necessary, to enable support for this edition. Set the shell # variable ac_prog_cc_stdc to indicate the edition. AC_DEFUN([_AC_PROG_CC_STDC_EDITION], [ac_prog_cc_stdc=no m4_map([_AC_PROG_CC_STDC_EDITION_TRY], [[11], [99], [89]])]) # _AC_PROG_CC_C89(ACTION-IF-SUPPORTED, ACTION-IF-NOT-SUPPORTED) # ------------------------------------------------------------- # Obsolete internal macro. No longer used by Autoconf itself, but # preserved for backward compatibility with pre-December 2020 versions # of Gnulib's std-gnu11.m4, which replaced the entire definition of # AC_PROG_CC *except* for this macro. Can be removed once everyone is # using Autoconf 2.70 and/or a current std-gnu11.m4. AC_DEFUN([_AC_PROG_CC_C89], [AC_REQUIRE([_AC_C_C89_TEST_GLOBALS])]dnl [AC_REQUIRE([_AC_C_C89_TEST_MAIN])]dnl [_AC_C_STD_TRY([c89], [$ac_c_conftest_c89_globals], [$ac_c_conftest_c89_main], m4_quote(m4_normalize(m4_defn([_AC_C_C89_OPTIONS]))), [$1], [$2])]) # AC_PROG_CC_C89 # -------------- # Do not use AU_ALIAS here and in AC_PROG_CC_C99 and AC_PROG_CC_STDC, # as that'd be incompatible with how Automake redefines AC_PROG_CC. See # <https://lists.gnu.org/archive/html/autoconf/2012-10/msg00048.html>. AU_DEFUN([AC_PROG_CC_C89], [AC_REQUIRE([AC_PROG_CC])], [$0 is obsolete; use AC_PROG_CC] ) # AC_PROG_CC_C99 # -------------- AU_DEFUN([AC_PROG_CC_C99], [AC_REQUIRE([AC_PROG_CC])], [$0 is obsolete; use AC_PROG_CC] ) # AC_PROG_CC_STDC # --------------- AU_DEFUN([AC_PROG_CC_STDC], [AC_REQUIRE([AC_PROG_CC])], [$0 is obsolete; use AC_PROG_CC] ) # AC_C_BACKSLASH_A # ---------------- AC_DEFUN([AC_C_BACKSLASH_A], [ AC_CACHE_CHECK([whether backslash-a works in strings], ac_cv_c_backslash_a, [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[ #if '\a' == 'a' syntax error; #endif char buf['\a' == 'a' ? -1 : 1]; buf[0] = '\a'; return buf[0] != "\a"[0]; ]])], [ac_cv_c_backslash_a=yes], [ac_cv_c_backslash_a=no])]) if test $ac_cv_c_backslash_a = yes; then AC_DEFINE(HAVE_C_BACKSLASH_A, 1, [Define if backslash-a works in C strings.]) fi ]) # AC_C_CROSS # ---------- # Has been merged into AC_PROG_CC. AU_DEFUN([AC_C_CROSS], []) # AC_C_CHAR_UNSIGNED # ------------------ AC_DEFUN([AC_C_CHAR_UNSIGNED], [AH_VERBATIM([__CHAR_UNSIGNED__], [/* Define to 1 if type `char' is unsigned and your compiler does not predefine this macro. */ #ifndef __CHAR_UNSIGNED__ # undef __CHAR_UNSIGNED__ #endif])dnl AC_CACHE_CHECK(whether char is unsigned, ac_cv_c_char_unsigned, [AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([AC_INCLUDES_DEFAULT([])], [((char) -1) < 0])], ac_cv_c_char_unsigned=no, ac_cv_c_char_unsigned=yes)]) if test $ac_cv_c_char_unsigned = yes; then AC_DEFINE(__CHAR_UNSIGNED__) fi ])# AC_C_CHAR_UNSIGNED # AC_C_BIGENDIAN ([ACTION-IF-TRUE], [ACTION-IF-FALSE], [ACTION-IF-UNKNOWN], # [ACTION-IF-UNIVERSAL]) # ------------------------------------------------------------------------- AC_DEFUN([AC_C_BIGENDIAN], [AH_VERBATIM([WORDS_BIGENDIAN], [/* Define WORDS_BIGENDIAN to 1 if your processor stores words with the most significant byte first (like Motorola and SPARC, unlike Intel). */ #if defined AC_APPLE_UNIVERSAL_BUILD # if defined __BIG_ENDIAN__ # define WORDS_BIGENDIAN 1 # endif #else # ifndef WORDS_BIGENDIAN # undef WORDS_BIGENDIAN # endif #endif])dnl AC_CACHE_CHECK([whether byte ordering is bigendian], [ac_cv_c_bigendian], [ac_cv_c_bigendian=unknown # See if we're dealing with a universal compiler. AC_COMPILE_IFELSE( [AC_LANG_SOURCE( [[#ifndef __APPLE_CC__ not a universal capable compiler #endif typedef int dummy; ]])], [ # Check for potential -arch flags. It is not universal unless # there are at least two -arch flags with different values. ac_arch= ac_prev= for ac_word in $CC $CFLAGS $CPPFLAGS $LDFLAGS; do if test -n "$ac_prev"; then case $ac_word in i?86 | x86_64 | ppc | ppc64) if test -z "$ac_arch" || test "$ac_arch" = "$ac_word"; then ac_arch=$ac_word else ac_cv_c_bigendian=universal break fi ;; esac ac_prev= elif test "x$ac_word" = "x-arch"; then ac_prev=arch fi done]) if test $ac_cv_c_bigendian = unknown; then # See if sys/param.h defines the BYTE_ORDER macro. AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[#include <sys/types.h> #include <sys/param.h> ]], [[#if ! (defined BYTE_ORDER && defined BIG_ENDIAN \ && defined LITTLE_ENDIAN && BYTE_ORDER && BIG_ENDIAN \ && LITTLE_ENDIAN) bogus endian macros #endif ]])], [# It does; now see whether it defined to BIG_ENDIAN or not. AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[#include <sys/types.h> #include <sys/param.h> ]], [[#if BYTE_ORDER != BIG_ENDIAN not big endian #endif ]])], [ac_cv_c_bigendian=yes], [ac_cv_c_bigendian=no])]) fi if test $ac_cv_c_bigendian = unknown; then # See if <limits.h> defines _LITTLE_ENDIAN or _BIG_ENDIAN (e.g., Solaris). AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[#include <limits.h> ]], [[#if ! (defined _LITTLE_ENDIAN || defined _BIG_ENDIAN) bogus endian macros #endif ]])], [# It does; now see whether it defined to _BIG_ENDIAN or not. AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[#include <limits.h> ]], [[#ifndef _BIG_ENDIAN not big endian #endif ]])], [ac_cv_c_bigendian=yes], [ac_cv_c_bigendian=no])]) fi if test $ac_cv_c_bigendian = unknown; then # Compile a test program. AC_RUN_IFELSE( [AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT], [[ /* Are we little or big endian? From Harbison&Steele. */ union { long int l; char c[sizeof (long int)]; } u; u.l = 1; return u.c[sizeof (long int) - 1] == 1; ]])], [ac_cv_c_bigendian=no], [ac_cv_c_bigendian=yes], [# Try to guess by grepping values from an object file. AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[unsigned short int ascii_mm[] = { 0x4249, 0x4765, 0x6E44, 0x6961, 0x6E53, 0x7953, 0 }; unsigned short int ascii_ii[] = { 0x694C, 0x5454, 0x656C, 0x6E45, 0x6944, 0x6E61, 0 }; int use_ascii (int i) { return ascii_mm[i] + ascii_ii[i]; } unsigned short int ebcdic_ii[] = { 0x89D3, 0xE3E3, 0x8593, 0x95C5, 0x89C4, 0x9581, 0 }; unsigned short int ebcdic_mm[] = { 0xC2C9, 0xC785, 0x95C4, 0x8981, 0x95E2, 0xA8E2, 0 }; int use_ebcdic (int i) { return ebcdic_mm[i] + ebcdic_ii[i]; } extern int foo; ]], [[return use_ascii (foo) == use_ebcdic (foo);]])], [if grep BIGenDianSyS conftest.$ac_objext >/dev/null; then ac_cv_c_bigendian=yes fi if grep LiTTleEnDian conftest.$ac_objext >/dev/null ; then if test "$ac_cv_c_bigendian" = unknown; then ac_cv_c_bigendian=no else # finding both strings is unlikely to happen, but who knows? ac_cv_c_bigendian=unknown fi fi])]) fi]) case $ac_cv_c_bigendian in #( yes) m4_default([$1], [AC_DEFINE([WORDS_BIGENDIAN], 1)]);; #( no) $2 ;; #( universal) dnl Note that AC_APPLE_UNIVERSAL_BUILD sorts less than WORDS_BIGENDIAN; dnl this is a necessity for proper config header operation. Warn if dnl the user did not specify a config header but is relying on the dnl default behavior for universal builds. m4_default([$4], [AC_CONFIG_COMMANDS_PRE([m4_ifset([AH_HEADER], [], [m4_warn([obsolete], [AC_C_BIGENDIAN should be used with AC_CONFIG_HEADERS])])])dnl AC_DEFINE([AC_APPLE_UNIVERSAL_BUILD],1, [Define if building universal (internal helper macro)])]) ;; #( *) m4_default([$3], [AC_MSG_ERROR([unknown endianness presetting ac_cv_c_bigendian=no (or yes) will help])]) ;; esac ])# AC_C_BIGENDIAN # AC_C__GENERIC # ------------- # Define HAVE_C__GENERIC if _Generic works, a la C11. AN_IDENTIFIER([_Generic], [AC_C__GENERIC]) AC_DEFUN([AC_C__GENERIC], [AC_CACHE_CHECK([for _Generic], ac_cv_c__Generic, [AC_COMPILE_IFELSE( [AC_LANG_SOURCE( [[int main (int argc, char **argv) { int a = _Generic (argc, int: argc = 1); int *b = &_Generic (argc, default: argc); char ***c = _Generic (argv, int: argc, default: argv ? &argv : 0); _Generic (1 ? 0 : b, int: a, default: b) = &argc; _Generic (a = 1, default: a) = 3; return a + !b + !c; } ]])], [ac_cv_c__Generic=yes], [ac_cv_c__Generic=no])]) if test $ac_cv_c__Generic = yes; then AC_DEFINE([HAVE_C__GENERIC], 1, [Define to 1 if C11-style _Generic works.]) fi ])# AC_C__GENERIC # AC_C_INLINE # ----------- # Do nothing if the compiler accepts the inline keyword. # Otherwise define inline to __inline__ or __inline if one of those work, # otherwise define inline to be empty. # # HP C version B.11.11.04 doesn't allow a typedef as the return value for an # inline function, only builtin types. # AN_IDENTIFIER([inline], [AC_C_INLINE]) AC_DEFUN([AC_C_INLINE], [AC_CACHE_CHECK([for inline], ac_cv_c_inline, [ac_cv_c_inline=no for ac_kw in inline __inline__ __inline; do AC_COMPILE_IFELSE([AC_LANG_SOURCE( [#ifndef __cplusplus typedef int foo_t; static $ac_kw foo_t static_foo (void) {return 0; } $ac_kw foo_t foo (void) {return 0; } #endif ])], [ac_cv_c_inline=$ac_kw]) test "$ac_cv_c_inline" != no && break done ]) AH_VERBATIM([inline], [/* Define to `__inline__' or `__inline' if that's what the C compiler calls it, or to nothing if 'inline' is not supported under any name. */ #ifndef __cplusplus #undef inline #endif]) case $ac_cv_c_inline in inline | yes) ;; *) case $ac_cv_c_inline in no) ac_val=;; *) ac_val=$ac_cv_c_inline;; esac cat >>confdefs.h <<_ACEOF #ifndef __cplusplus #define inline $ac_val #endif _ACEOF ;; esac ])# AC_C_INLINE # AC_C_CONST # ---------- AC_DEFUN([AC_C_CONST], [AC_CACHE_CHECK([for an ANSI C-conforming const], ac_cv_c_const, [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[ #ifndef __cplusplus /* Ultrix mips cc rejects this sort of thing. */ typedef int charset[2]; const charset cs = { 0, 0 }; /* SunOS 4.1.1 cc rejects this. */ char const *const *pcpcc; char **ppc; /* NEC SVR4.0.2 mips cc rejects this. */ struct point {int x, y;}; static struct point const zero = {0,0}; /* IBM XL C 1.02.0.0 rejects this. It does not let you subtract one const X* pointer from another in an arm of an if-expression whose if-part is not a constant expression */ const char *g = "string"; pcpcc = &g + (g ? g-g : 0); /* HPUX 7.0 cc rejects these. */ ++pcpcc; ppc = (char**) pcpcc; pcpcc = (char const *const *) ppc; { /* SCO 3.2v4 cc rejects this sort of thing. */ char tx; char *t = &tx; char const *s = 0 ? (char *) 0 : (char const *) 0; *t++ = 0; if (s) return 0; } { /* Someone thinks the Sun supposedly-ANSI compiler will reject this. */ int x[] = {25, 17}; const int *foo = &x[0]; ++foo; } { /* Sun SC1.0 ANSI compiler rejects this -- but not the above. */ typedef const int *iptr; iptr p = 0; ++p; } { /* IBM XL C 1.02.0.0 rejects this sort of thing, saying "k.c", line 2.27: 1506-025 (S) Operand must be a modifiable lvalue. */ struct s { int j; const int *ap[3]; } bx; struct s *b = &bx; b->j = 5; } { /* ULTRIX-32 V3.1 (Rev 9) vcc rejects this */ const int foo = 10; if (!foo) return 0; } return !cs[0] && !zero.x; #endif ]])], [ac_cv_c_const=yes], [ac_cv_c_const=no])]) if test $ac_cv_c_const = no; then AC_DEFINE(const,, [Define to empty if `const' does not conform to ANSI C.]) fi ])# AC_C_CONST # AC_C_RESTRICT # ------------- # based on acx_restrict.m4, from the GNU Autoconf Macro Archive # # Determine whether the C/C++ compiler supports the "restrict" keyword # introduced in ANSI C99, or an equivalent. Define "restrict" to the alternate # spelling, if any; these are more likely to work in both C and C++ compilers of # the same family, and in the presence of varying compiler options. If only # plain "restrict" works, do nothing. Here are some variants: # - GCC supports both __restrict and __restrict__ # - older DEC Alpha C compilers support only __restrict # - _Restrict is the only spelling accepted by Sun WorkShop 6 update 2 C # Otherwise, define "restrict" to be empty. AN_IDENTIFIER([restrict], [AC_C_RESTRICT]) AC_DEFUN([AC_C_RESTRICT], [AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict], [ac_cv_c_restrict=no # Put '__restrict__' first, to avoid problems with glibc and non-GCC; see: # https://lists.gnu.org/archive/html/bug-autoconf/2016-02/msg00006.html # Put 'restrict' last, because C++ lacks it. for ac_kw in __restrict__ __restrict _Restrict restrict; do AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[typedef int *int_ptr; int foo (int_ptr $ac_kw ip) { return ip[0]; } int bar (int [$ac_kw]); /* Catch GCC bug 14050. */ int bar (int ip[$ac_kw]) { return ip[0]; } ]], [[int s[1]; int *$ac_kw t = s; t[0] = 0; return foo (t) + bar (t); ]])], [ac_cv_c_restrict=$ac_kw]) test "$ac_cv_c_restrict" != no && break done ]) AH_VERBATIM([restrict], [/* Define to the equivalent of the C99 'restrict' keyword, or to nothing if this is not supported. Do not define if restrict is supported only directly. */ #undef restrict /* Work around a bug in older versions of Sun C++, which did not #define __restrict__ or support _Restrict or __restrict__ even though the corresponding Sun C compiler ended up with "#define restrict _Restrict" or "#define restrict __restrict__" in the previous line. This workaround can be removed once we assume Oracle Developer Studio 12.5 (2016) or later. */ #if defined __SUNPRO_CC && !defined __RESTRICT && !defined __restrict__ # define _Restrict # define __restrict__ #endif]) case $ac_cv_c_restrict in restrict) ;; no) AC_DEFINE([restrict], []) ;; *) AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;; esac ])# AC_C_RESTRICT # AC_C_VOLATILE # ------------- # Note that, unlike const, #defining volatile to be the empty string can # actually turn a correct program into an incorrect one, since removing # uses of volatile actually grants the compiler permission to perform # optimizations that could break the user's code. So, do not #define # volatile away unless it is really necessary to allow the user's code # to compile cleanly. Benign compiler failures should be tolerated. AC_DEFUN([AC_C_VOLATILE], [AC_CACHE_CHECK([for working volatile], ac_cv_c_volatile, [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [ volatile int x; int * volatile y = (int *) 0; return !x && !y;])], [ac_cv_c_volatile=yes], [ac_cv_c_volatile=no])]) if test $ac_cv_c_volatile = no; then AC_DEFINE(volatile,, [Define to empty if the keyword `volatile' does not work. Warning: valid code using `volatile' can become incorrect without. Disable with care.]) fi ])# AC_C_VOLATILE # AC_C_STRINGIZE # -------------- # Checks if `#' can be used to glue strings together at the CPP level. # Defines HAVE_STRINGIZE if positive. AC_DEFUN([AC_C_STRINGIZE], [AC_CACHE_CHECK([for preprocessor stringizing operator], [ac_cv_c_stringize], [AC_EGREP_CPP([@%:@teststring], [@%:@define x(y) #y char *s = x(teststring);], [ac_cv_c_stringize=no], [ac_cv_c_stringize=yes])]) if test $ac_cv_c_stringize = yes; then AC_DEFINE(HAVE_STRINGIZE, 1, [Define to 1 if cpp supports the ANSI @%:@ stringizing operator.]) fi ])# AC_C_STRINGIZE # AC_C_PROTOTYPES # --------------- # Check if the C compiler supports prototypes, included if it needs # options. AC_DEFUN([AC_C_PROTOTYPES], [AC_REQUIRE([AC_PROG_CC])dnl if test "$ac_prog_cc_stdc" != no; then AC_DEFINE(PROTOTYPES, 1, [Define to 1 if the C compiler supports function prototypes.]) AC_DEFINE(__PROTOTYPES, 1, [Define like PROTOTYPES; this can be used by system headers.]) fi ])# AC_C_PROTOTYPES # AC_C_FLEXIBLE_ARRAY_MEMBER # -------------------------- # Check whether the C compiler supports flexible array members. AC_DEFUN([AC_C_FLEXIBLE_ARRAY_MEMBER], [ AC_CACHE_CHECK([for flexible array members], ac_cv_c_flexmember, [AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[#include <stdlib.h> #include <stdio.h> #include <stddef.h> struct s { int n; double d[]; };]], [[int m = getchar (); struct s *p = (struct s *) malloc (offsetof (struct s, d) + m * sizeof (double)); p->d[0] = 0.0; return p->d != (double *) NULL;]])], [ac_cv_c_flexmember=yes], [ac_cv_c_flexmember=no])]) if test $ac_cv_c_flexmember = yes; then AC_DEFINE([FLEXIBLE_ARRAY_MEMBER], [], [Define to nothing if C supports flexible array members, and to 1 if it does not. That way, with a declaration like `struct s { int n; double d@<:@FLEXIBLE_ARRAY_MEMBER@:>@; };', the struct hack can be used with pre-C99 compilers. When computing the size of such an object, don't use 'sizeof (struct s)' as it overestimates the size. Use 'offsetof (struct s, d)' instead. Don't use 'offsetof (struct s, d@<:@0@:>@)', as this doesn't work with MSVC and with C++ compilers.]) else AC_DEFINE([FLEXIBLE_ARRAY_MEMBER], 1) fi ]) # AC_C_VARARRAYS # -------------- # Check whether the C compiler supports variable-length arrays. AC_DEFUN([AC_C_VARARRAYS], [ AC_CACHE_CHECK([for variable-length arrays], ac_cv_c_vararrays, [AC_EGREP_CPP([defined], [#ifdef __STDC_NO_VLA__ defined #endif ], [ac_cv_c_vararrays='no: __STDC_NO_VLA__ is defined'], [AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[/* Test for VLA support. This test is partly inspired from examples in the C standard. Use at least two VLA functions to detect the GCC 3.4.3 bug described in: https://lists.gnu.org/archive/html/bug-gnulib/2014-08/msg00014.html */ #ifdef __STDC_NO_VLA__ syntax error; #else extern int n; int B[100]; int fvla (int m, int C[m][m]); int simple (int count, int all[static count]) { return all[count - 1]; } int fvla (int m, int C[m][m]) { typedef int VLA[m][m]; VLA x; int D[m]; static int (*q)[m] = &B; int (*s)[n] = q; return C && &x[0][0] == &D[0] && &D[0] == s[0]; } #endif ]])], [ac_cv_c_vararrays=yes], [ac_cv_c_vararrays=no])])]) if test "$ac_cv_c_vararrays" = yes; then dnl This is for compatibility with Autoconf 2.61-2.69. AC_DEFINE([HAVE_C_VARARRAYS], 1, [Define to 1 if C supports variable-length arrays.]) elif test "$ac_cv_c_vararrays" = no; then AC_DEFINE([__STDC_NO_VLA__], 1, [Define to 1 if C does not support variable-length arrays, and if the compiler does not already define this.]) fi ]) # AC_C_TYPEOF # ----------- # Check if the C compiler supports GCC's typeof syntax. # The test case provokes incompatibilities in the Sun C compilers # (both Solaris 8 and Solaris 10). AC_DEFUN([AC_C_TYPEOF], [ AC_CACHE_CHECK([for typeof syntax and keyword spelling], ac_cv_c_typeof, [ac_cv_c_typeof=no for ac_kw in typeof __typeof__ no; do test $ac_kw = no && break AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[ int value; typedef struct { char a [1 + ! (($ac_kw (value)) (($ac_kw (value)) 0 < ($ac_kw (value)) -1 ? ($ac_kw (value)) - 1 : ~ (~ ($ac_kw (value)) 0 << sizeof ($ac_kw (value)))))]; } ac__typeof_type_; return (! ((void) ((ac__typeof_type_ *) 0), 0)); ]])], [ac_cv_c_typeof=$ac_kw]) test $ac_cv_c_typeof != no && break done]) if test $ac_cv_c_typeof != no; then AC_DEFINE([HAVE_TYPEOF], 1, [Define to 1 if typeof works with your compiler.]) if test $ac_cv_c_typeof != typeof; then AC_DEFINE_UNQUOTED([typeof], [$ac_cv_c_typeof], [Define to __typeof__ if your compiler spells it that way.]) fi fi ]) # _AC_LANG_OPENMP # --------------- # Expands to some language dependent source code for testing the presence of # OpenMP. AC_DEFUN([_AC_LANG_OPENMP], [AC_LANG_SOURCE([_AC_LANG_DISPATCH([$0], _AC_LANG, $@)])]) # _AC_LANG_OPENMP(C) # ------------------ m4_define([_AC_LANG_OPENMP(C)], [ #ifndef _OPENMP #error "OpenMP not supported" #endif #include <omp.h> int main (void) { return omp_get_num_threads (); } ]) # _AC_LANG_OPENMP(C++) # -------------------- m4_copy([_AC_LANG_OPENMP(C)], [_AC_LANG_OPENMP(C++)]) # _AC_LANG_OPENMP(Fortran 77) # --------------------------- m4_define([_AC_LANG_OPENMP(Fortran 77)], [ program main implicit none !$ integer tid tid = 42 call omp_set_num_threads(2) end ]) # _AC_LANG_OPENMP(Fortran) # ------------------------ m4_copy([_AC_LANG_OPENMP(Fortran 77)], [_AC_LANG_OPENMP(Fortran)]) # AC_OPENMP # --------- # Check which options need to be passed to the C compiler to support OpenMP. # Set the OPENMP_CFLAGS / OPENMP_CXXFLAGS / OPENMP_FFLAGS variable to these # options. # The options are necessary at compile time (so the #pragmas are understood) # and at link time (so the appropriate library is linked with). # This macro takes care to not produce redundant options if $CC $CFLAGS already # supports OpenMP. # # For each candidate option, we do a compile test first, then a link test; # if the compile test succeeds but the link test fails, that means we have # found the correct option but it doesn't work because the libraries are # broken. (This can happen, for instance, with SunPRO C and a bad combination # of operating system patches.) # # Several of the options in our candidate list can be misinterpreted by # compilers that don't use them to activate OpenMP support; for example, # many compilers understand "-openmp" to mean "write output to a file # named 'penmp'" rather than "enable OpenMP". We can't completely avoid # the possibility of clobbering files named 'penmp' or 'mp' in configure's # working directory; therefore, this macro will bomb out if any such file # already exists when it's invoked. AC_DEFUN([AC_OPENMP], [AC_REQUIRE([_AC_OPENMP_SAFE_WD])]dnl [AC_ARG_ENABLE([openmp], [AS_HELP_STRING([--disable-openmp], [do not use OpenMP])])]dnl [ OPENMP_[]_AC_LANG_PREFIX[]FLAGS= if test "$enable_openmp" != no; then AC_CACHE_CHECK([for $[]_AC_CC[] option to support OpenMP], [ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp], [ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp='not found' dnl Try these flags: dnl (on by default) '' dnl GCC >= 4.2 -fopenmp dnl SunPRO C -xopenmp dnl Intel C -openmp dnl SGI C, PGI C -mp dnl Tru64 Compaq C -omp dnl IBM XL C (AIX, Linux) -qsmp=omp dnl Cray CCE -homp dnl NEC SX -Popenmp dnl Lahey Fortran (Linux) --openmp for ac_option in '' -fopenmp -xopenmp -openmp -mp -omp -qsmp=omp -homp \ -Popenmp --openmp; do ac_save_[]_AC_LANG_PREFIX[]FLAGS=$[]_AC_LANG_PREFIX[]FLAGS _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $ac_option" AC_COMPILE_IFELSE([_AC_LANG_OPENMP], [AC_LINK_IFELSE([_AC_LANG_OPENMP], [ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp=$ac_option], [ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp='unsupported'])]) _AC_LANG_PREFIX[]FLAGS=$ac_save_[]_AC_LANG_PREFIX[]FLAGS if test "$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp" != 'not found'; then break fi done if test "$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp" = 'not found'; then ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp='unsupported' elif test "$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp" = ''; then ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp='none needed' fi dnl _AC_OPENMP_SAFE_WD checked that these files did not exist before we dnl started probing for OpenMP support, so if they exist now, they were dnl created by the probe loop and it's safe to delete them. rm -f penmp mp]) if test "$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp" != 'unsupported' && \ test "$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp" != 'none needed'; then OPENMP_[]_AC_LANG_PREFIX[]FLAGS="$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp" fi fi AC_SUBST([OPENMP_]_AC_LANG_PREFIX[FLAGS]) ]) # _AC_OPENMP_SAFE_WD # ------------------ # AC_REQUIREd by AC_OPENMP. Checks both at autoconf time and at # configure time for files that AC_OPENMP clobbers. AC_DEFUN([_AC_OPENMP_SAFE_WD], [m4_syscmd([test ! -e penmp && test ! -e mp])]dnl [m4_if(sysval, [0], [], [m4_fatal(m4_normalize( [AC_OPENMP clobbers files named 'mp' and 'penmp'. To use AC_OPENMP you must not have either of these files at the top level of your source tree.]))])]dnl [if test -e penmp || test -e mp; then AC_MSG_ERROR(m4_normalize( [AC@&t@_OPENMP clobbers files named 'mp' and 'penmp'. Aborting configure because one of these files already exists.])) fi]) # ---------------------------------- # # 4b. C++ compiler characteristics. # # ---------------------------------- # # See the long comment at the beginning of section 4a for rationale # for these macros, and constraints on how the test programs should # be written. # # The C++98 freestanding headers are: # <cstdarg> <cstddef> <cstdlib> <exception> <limits> <new> <typeinfo> # C++11 adds: # <atomic> <cfloat> <ciso646> <climits> <cstdalign> <cstdbool> # <cstdint> <initializer_list> <type_traits> # # No other headers can safely be included. Therefore, almost no C++ # standard library features are tested for. Use AC_CHECK_HEADER, etc. # if you need that. AC_DEFUN([_AC_CXX_CXX98_TEST_GLOBALS], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C++ compiler supports C++98 (global declarations) ac_cxx_conftest_cxx98_globals=' // Does the compiler advertise C++98 conformance? #if !defined __cplusplus || __cplusplus < 199711L # error "Compiler does not advertise C++98 conformance" #endif // These inclusions are to reject old compilers that // lack the unsuffixed header files. #include <cstdlib> #include <exception> // <cassert> and <cstring> are *not* freestanding headers in C++98. extern void assert (int); namespace std { extern int strcmp (const char *, const char *); } // Namespaces, exceptions, and templates were all added after "C++ 2.0". using std::exception; using std::strcmp; namespace { void test_exception_syntax() { try { throw "test"; } catch (const char *s) { // Extra parentheses suppress a warning when building autoconf itself, // due to lint rules shared with more typical C programs. assert (!(strcmp) (s, "test")); } } template <typename T> struct test_template { T const val; explicit test_template(T t) : val(t) {} template <typename U> T add(U u) { return static_cast<T>(u) + val; } }; } // anonymous namespace ' ]])]) AC_DEFUN([_AC_CXX_CXX98_TEST_MAIN], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C++ compiler supports C++98 (body of main) ac_cxx_conftest_cxx98_main=' assert (argc); assert (! argv[0]); { test_exception_syntax (); test_template<double> tt (2.0); assert (tt.add (4) == 6.0); assert (true && !false); } ' ]])]) AC_DEFUN([_AC_CXX_CXX11_TEST_GLOBALS], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C++ compiler supports C++11 (global declarations) ac_cxx_conftest_cxx11_globals=' // Does the compiler advertise C++ 2011 conformance? #if !defined __cplusplus || __cplusplus < 201103L # error "Compiler does not advertise C++11 conformance" #endif namespace cxx11test { constexpr int get_val() { return 20; } struct testinit { int i; double d; }; class delegate { public: delegate(int n) : n(n) {} delegate(): delegate(2354) {} virtual int getval() { return this->n; }; protected: int n; }; class overridden : public delegate { public: overridden(int n): delegate(n) {} virtual int getval() override final { return this->n * 2; } }; class nocopy { public: nocopy(int i): i(i) {} nocopy() = default; nocopy(const nocopy&) = delete; nocopy & operator=(const nocopy&) = delete; private: int i; }; // for testing lambda expressions template <typename Ret, typename Fn> Ret eval(Fn f, Ret v) { return f(v); } // for testing variadic templates and trailing return types template <typename V> auto sum(V first) -> V { return first; } template <typename V, typename... Args> auto sum(V first, Args... rest) -> V { return first + sum(rest...); } } ' ]])]) AC_DEFUN([_AC_CXX_CXX11_TEST_MAIN], [m4_divert_text([INIT_PREPARE], [[# Test code for whether the C++ compiler supports C++11 (body of main) ac_cxx_conftest_cxx11_main=' { // Test auto and decltype auto a1 = 6538; auto a2 = 48573953.4; auto a3 = "String literal"; int total = 0; for (auto i = a3; *i; ++i) { total += *i; } decltype(a2) a4 = 34895.034; } { // Test constexpr short sa[cxx11test::get_val()] = { 0 }; } { // Test initializer lists cxx11test::testinit il = { 4323, 435234.23544 }; } { // Test range-based for int array[] = {9, 7, 13, 15, 4, 18, 12, 10, 5, 3, 14, 19, 17, 8, 6, 20, 16, 2, 11, 1}; for (auto &x : array) { x += 23; } } { // Test lambda expressions using cxx11test::eval; assert (eval ([](int x) { return x*2; }, 21) == 42); double d = 2.0; assert (eval ([&](double x) { return d += x; }, 3.0) == 5.0); assert (d == 5.0); assert (eval ([=](double x) mutable { return d += x; }, 4.0) == 9.0); assert (d == 5.0); } { // Test use of variadic templates using cxx11test::sum; auto a = sum(1); auto b = sum(1, 2); auto c = sum(1.0, 2.0, 3.0); } { // Test constructor delegation cxx11test::delegate d1; cxx11test::delegate d2(); cxx11test::delegate d3(45); } { // Test override and final cxx11test::overridden o1(55464); } { // Test nullptr char *c = nullptr; } { // Test template brackets test_template<::test_template<int>> v(test_template<int>(12)); } { // Unicode literals char const *utf8 = u8"UTF-8 string \u2500"; char16_t const *utf16 = u"UTF-8 string \u2500"; char32_t const *utf32 = U"UTF-32 string \u2500"; } ' ]])]) AC_DEFUN([_AC_CXX_CXX98_TEST_PROGRAM], [AC_REQUIRE([_AC_CXX_CXX98_TEST_GLOBALS])dnl AC_REQUIRE([_AC_CXX_CXX98_TEST_MAIN])dnl m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C++98 (complete). ac_cxx_conftest_cxx98_program="${ac_cxx_conftest_cxx98_globals} int main (int argc, char **argv) { int ok = 0; ${ac_cxx_conftest_cxx98_main} return ok; } " ]])]) AC_DEFUN([_AC_CXX_CXX11_TEST_PROGRAM], [AC_REQUIRE([_AC_CXX_CXX98_TEST_GLOBALS])dnl AC_REQUIRE([_AC_CXX_CXX98_TEST_MAIN])dnl AC_REQUIRE([_AC_CXX_CXX11_TEST_GLOBALS])dnl AC_REQUIRE([_AC_CXX_CXX11_TEST_MAIN])dnl m4_divert_text([INIT_PREPARE], [[# Test code for whether the C compiler supports C++11 (complete). ac_cxx_conftest_cxx11_program="${ac_cxx_conftest_cxx98_globals} ${ac_cxx_conftest_cxx11_globals} int main (int argc, char **argv) { int ok = 0; ${ac_cxx_conftest_cxx98_main} ${ac_cxx_conftest_cxx11_main} return ok; } " ]])]) # _AC_CXX_CXX98_OPTIONS # --------------------- # Whitespace-separated list of options that might put the C++ compiler # into a mode conforming to ISO C++ 1998 with extensions. Do not try # "strictly conforming" modes (e.g. gcc's -std=c++98); they break some # systems' header files. If more than one option is needed, put # shell quotes around the group. # # GCC -std=gnu++98 # Intel ICC -std=c++98 # Note: because -std=c++98 puts GCC in strictly conforming mode, # this option must be tested *after* -std=gnu++98. # IBM XL C -qlanglvl=extended # HP aC++ -AA # Solaris N/A (default) # Tru64 N/A (default, but -std gnu could be used) m4_define([_AC_CXX_CXX98_OPTIONS], [ -std=gnu++98 -std=c++98 -qlanglvl=extended -AA ]) # _AC_CXX_CXX11_OPTIONS # --------------------- # Whitespace-separated list of options that might put the C++ compiler # into a mode conforming to ISO C++ 2011 with extensions. Do not try # "strictly conforming" modes (e.g. gcc's -std=c++11); they break some # systems' header files. If more than one option is needed, put # shell quotes around the group. # # GCC -std=gnu++11, -std=gnu++0x # Intel ICC -std=c++11, -std=c++0x # Note: because -std=c++11 puts GCC in strictly conforming mode, # these options must be tested *after* -std=gnu++11. # IBM XL C -qlanglvl=extended0x (pre-V12.1) # HP aC++ -AA # Solaris N/A (no support) # Tru64 N/A (no support) m4_define([_AC_CXX_CXX11_OPTIONS], [ -std=gnu++11 -std=gnu++0x -std=c++11 -std=c++0x -qlanglvl=extended0x -AA ]) # _AC_PROG_CXX_STDCXX_EDITION_TRY(EDITION) # ---------------------------------------- # Subroutine of _AC_PROG_CXX_STDCXX_EDITION. Not to be called directly. # # Check whether the C++ compiler accepts features of EDITION of the # C++ standard. EDITION should be a two-digit year (e.g. 98, 11). # (FIXME: Switch to four-digit years for futureproofing.) # This is done by compiling the test program defined by # _AC_C_CXX{EDITION}_TEST_PROGRAM, first with no additional # command-line options, and then with each of the options # in the space-separated list defined by _AC_C_CXX{EDITION}_OPTIONS. # # If we find a way to make the test program compile, set cache variable # ac_cv_prog_cxx_cxxEDITION to the options required (if any), and add those # options to $CXX. Set shell variable ac_prog_cxx_stdcxx to `cxxEDITION', # and set shell variable ac_cv_prog_cxx_stdcxx to the options required. # (Neither of these variables is AC_SUBSTed. ac_cv_prog_cxx_stdcxx used # to be a cache variable and is preserved with this name for backward # compatibility.) Otherwise, ac_cv_prog_cxx_cxxEDITION is set to `no' # and the other variables are not changed. # # If ac_prog_cxx_stdcxx is already set to a value other than `no', # the shell code produced by this macro does nothing. This is so # _AC_PROG_CXX_STDCXX_EDITION can use m4_map to iterate through # all the editions. AC_DEFUN([_AC_PROG_CXX_STDCXX_EDITION_TRY], [AC_LANG_ASSERT([C++])]dnl [AC_REQUIRE([_AC_CXX_CXX$1_TEST_PROGRAM])]dnl [AS_IF([test x$ac_prog_cxx_stdcxx = xno], [AC_MSG_CHECKING([for $CXX option to enable C++$1 features]) AC_CACHE_VAL([ac_cv_prog_cxx_cxx$1], [ac_cv_prog_cxx_cxx$1=no ac_save_CXX=$CXX AC_LANG_CONFTEST([AC_LANG_DEFINES_PROVIDED][$][ac_cxx_conftest_cxx$1_program]) for ac_arg in '' m4_normalize(m4_defn([_AC_CXX_CXX$1_OPTIONS])) do CXX="$ac_save_CXX $ac_arg" _AC_COMPILE_IFELSE([], [ac_cv_prog_cxx_cxx$1=$ac_arg]) test "x$ac_cv_prog_cxx_cxx$1" != "xno" && break done rm -f conftest.$ac_ext CXX=$ac_save_CXX]) AS_IF([test "x$ac_cv_prog_cxx_cxx$1" = xno], [AC_MSG_RESULT([unsupported])], [AS_IF([test "x$ac_cv_prog_cxx_cxx$1" = x], [AC_MSG_RESULT([none needed])], [AC_MSG_RESULT([$ac_cv_prog_cxx_cxx$1]) CXX="$CXX $ac_cv_prog_cxx_cxx$1"]) ac_cv_prog_cxx_stdcxx=$ac_cv_prog_cxx_cxx$1 ac_prog_cxx_stdcxx=cxx$1])]) ]) # _AC_PROG_CXX_STDCXX_EDITION # --------------------------- # Detect the most recent edition of the ISO C++ standard that is # supported by the C++ compiler. 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