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Diffstat (limited to 'm4/compiler-features.m4')
| -rw-r--r-- | m4/compiler-features.m4 | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/m4/compiler-features.m4 b/m4/compiler-features.m4 new file mode 100644 index 000000000000..840f292383d5 --- /dev/null +++ b/m4/compiler-features.m4 @@ -0,0 +1,122 @@ +dnl Copyright 2010 The Kyua Authors. +dnl All rights reserved. +dnl +dnl Redistribution and use in source and binary forms, with or without +dnl modification, are permitted provided that the following conditions are +dnl met: +dnl +dnl * Redistributions of source code must retain the above copyright +dnl notice, this list of conditions and the following disclaimer. +dnl * Redistributions in binary form must reproduce the above copyright +dnl notice, this list of conditions and the following disclaimer in the +dnl documentation and/or other materials provided with the distribution. +dnl * Neither the name of Google Inc. nor the names of its contributors +dnl may be used to endorse or promote products derived from this software +dnl without specific prior written permission. +dnl +dnl THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +dnl "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +dnl LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +dnl A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +dnl OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +dnl SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +dnl LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +dnl DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +dnl THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +dnl (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +dnl OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +dnl +dnl KYUA_ATTRIBUTE_NORETURN +dnl +dnl Checks if the current compiler has a way to mark functions that do not +dnl return and defines ATTRIBUTE_NORETURN to the appropriate string. +dnl +AC_DEFUN([KYUA_ATTRIBUTE_NORETURN], [ + dnl This check is overly simple and should be fixed. For example, + dnl Sun's cc does support the noreturn attribute but CC (the C++ + dnl compiler) does not. And in that case, CC just raises a warning + dnl during compilation, not an error. + AC_CACHE_CHECK( + [whether __attribute__((noreturn)) is supported], + [kyua_cv_attribute_noreturn], [ + AC_RUN_IFELSE([AC_LANG_PROGRAM([], [ +#if ((__GNUC__ == 2 && __GNUC_MINOR__ >= 5) || __GNUC__ > 2) + return 0; +#else + return 1; +#endif + ])], + [kyua_cv_attribute_noreturn=yes], + [kyua_cv_attribute_noreturn=no]) + ]) + if test "${kyua_cv_attribute_noreturn}" = yes; then + attribute_value="__attribute__((noreturn))" + else + attribute_value="" + fi + AC_SUBST([ATTRIBUTE_NORETURN], [${attribute_value}]) +]) + + +dnl +dnl KYUA_ATTRIBUTE_PURE +dnl +dnl Checks if the current compiler has a way to mark functions as pure. +dnl +AC_DEFUN([KYUA_ATTRIBUTE_PURE], [ + AC_CACHE_CHECK( + [whether __attribute__((__pure__)) is supported], + [kyua_cv_attribute_pure], [ + AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([ +static int function(int, int) __attribute__((__pure__)); + +static int +function(int a, int b) +{ + return a + b; +}], [ + return function(3, 4); +])], + [kyua_cv_attribute_pure=yes], + [kyua_cv_attribute_pure=no]) + ]) + if test "${kyua_cv_attribute_pure}" = yes; then + attribute_value="__attribute__((__pure__))" + else + attribute_value="" + fi + AC_SUBST([ATTRIBUTE_PURE], [${attribute_value}]) +]) + + +dnl +dnl KYUA_ATTRIBUTE_UNUSED +dnl +dnl Checks if the current compiler has a way to mark parameters as unused +dnl so that the -Wunused-parameter warning can be avoided. +dnl +AC_DEFUN([KYUA_ATTRIBUTE_UNUSED], [ + AC_CACHE_CHECK( + [whether __attribute__((__unused__)) is supported], + [kyua_cv_attribute_unused], [ + AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([ +static void +function(int a __attribute__((__unused__))) +{ +}], [ + function(3); + return 0; +])], + [kyua_cv_attribute_unused=yes], + [kyua_cv_attribute_unused=no]) + ]) + if test "${kyua_cv_attribute_unused}" = yes; then + attribute_value="__attribute__((__unused__))" + else + attribute_value="" + fi + AC_SUBST([ATTRIBUTE_UNUSED], [${attribute_value}]) +]) |