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AX_FUNC_POSIX_MEMALIGN
0.5.57 : pakin
Scott Pakin <pakin@uiuc.edu>
Some versions of posix_memalign (notably glibc 2.2.5) incorrectly apply their power-of-two check to the size argument, not the alignment argument. AX_FUNC_POSIX_MEMALIGN defines HAVE_POSIX_MEMALIGN if the power-of-two check is correctly applied to the alignment argument.
AC_DEFUN([AX_FUNC_POSIX_MEMALIGN], [AC_CACHE_CHECK([for working posix_memalign], [ax_cv_func_posix_memalign_works], [AC_TRY_RUN([ #include <stdlib.h> int main () { void *buffer; /* Some versions of glibc incorrectly perform the alignment check on * the size word. */ exit (posix_memalign (&buffer, sizeof(void *), 123) != 0); } ], [ax_cv_func_posix_memalign_works=yes], [ax_cv_func_posix_memalign_works=no], [ax_cv_func_posix_memalign_works=no])]) if test "$ax_cv_func_posix_memalign_works" = "yes" ; then AC_DEFINE([HAVE_POSIX_MEMALIGN], [1], [Define to 1 if `posix_memalign' works.]) fi ])