X-Git-Url: https://diplodocus.org/git/nmh/blobdiff_plain/f877b4ce909e65e97cf9259b7113078b93587653..5b7691dba53ba51b284988c90b9aed1fd78d8ed4:/configure.ac

diff --git a/configure.ac b/configure.ac
index 234ff3c4..2c76cea6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -587,13 +587,15 @@ dnl ----------------
 dnl CHECK STRUCTURES
 dnl ----------------
 
-dnl FIXME: This test could work on Linux if _BSD_SOURCE was #define'd
-dnl according to localtime(3).
-dnl
 dnl For platforms such as FreeBSD that have tm_gmtoff in struct tm.
 dnl (FreeBSD has a timezone() function but not a timezone global
 dnl variable that is visible).
-AC_CHECK_MEMBERS([struct tm.tm_gmtoff],,,[#include <time.h>])
+dnl On Linux, $AM_CPPFLAGS contains -D_GNU_SOURCE, which makes
+dnl tm_gmtoff visible.
+nmh_saved_CPPFLAGS="$CPPFLAGS"
+CPPFLAGS="$AM_CPPFLAGS $CPPFLAGS"
+AC_CHECK_MEMBERS([struct tm.tm_gmtoff],,,[[#include <time.h>]])
+CPPFLAGS="$nmh_saved_CPPFLAGS"
 
 AC_STRUCT_DIRENT_D_TYPE