[gdm] build: Don't automatically use _FORTIFY_SOURCE

[Colin Walters <walters src gnome org>]

commit beebfcd47cc63eb25b9e4921f78206447b85a517
Author: Colin Walters <walters verbum org>
Date:   Mon Dec 3 14:05:40 2012 -0500

    build: Don't automatically use _FORTIFY_SOURCE
    
    OS builders can add this flag externally if desired.  The problem with
    us doing this unconditionally, it causes the cpp to spam us with
    warnings if we're building without optimization (i.e. CFLAGS='-ggdb
    -O0') which I often do so I can use gdb.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=689569

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index a778990..5f57999 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1433,7 +1433,7 @@ if test "$GCC" = "yes" -a "$set_more_warnings" != "no"; then
         -Wall \
         -Wchar-subscripts -Wmissing-declarations -Wmissing-prototypes \
         -Wnested-externs -Wpointer-arith \
-        -Wcast-align -Wsign-compare -Wp,-D_FORTIFY_SOURCE=2 \
+        -Wcast-align -Wsign-compare \
         $CFLAGS"
 
         for option in -Wno-strict-aliasing -Wno-sign-compare; do