acinclude/ac_check_define.m4

AC_DEFUN([AC_CHECK_DEFINE],[AC_REQUIRE([AC_PROG_CPP])dnl
  AC_CACHE_CHECK(for $1 in $2, ac_cv_define_$1,
    AC_EGREP_CPP([YES_IS_DEFINED], [
#include <$2>
#ifdef $1
YES_IS_DEFINED
#endif
    ], ac_cv_define_$1=yes, ac_cv_define_$1=no)
  )
  if test "$ac_cv_define_$1" = "yes" ; then
    AC_DEFINE([HAVE_$1],[],[Added by AC_CHECK_DEFINE])
  fi
])dnl
ac_check_define.m4: AC_REQUIRE([AC_PROG_CPP]) -- fixes bug #5234. 2020-09-16 08:00:20 +03:00			`AC_DEFUN([AC_CHECK_DEFINE],[AC_REQUIRE([AC_PROG_CPP])dnl`
Fixed crash if initialization of EGL failed but was tried again later. The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly uninitialized data structure if loading the library first failed. A later try to use EGL then skipped initialization and assumed it was previously successful because the data structure now already existed. This led to at least one crash in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was dereferenced to make a call to eglBindAPI(). 2015-06-21 17:33:46 +02:00			`AC_CACHE_CHECK(for $1 in $2, ac_cv_define_$1,`
			`AC_EGREP_CPP([YES_IS_DEFINED], [`
			`#include <$2>`
			`#ifdef $1`
			`YES_IS_DEFINED`
			`#endif`
			`], ac_cv_define_$1=yes, ac_cv_define_$1=no)`
			`)`
			`if test "$ac_cv_define_$1" = "yes" ; then`
			`AC_DEFINE([HAVE_$1],[],[Added by AC_CHECK_DEFINE])`
			`fi`
			`])dnl`
ac_check_define.m4: remove stray AC_DEFINE outside of the macro definition cf.: bug #5234 -- generated configure script does not change. 2020-09-16 22:20:02 +03:00