build: silence some compiler warnings from gnulib

Gnulib claims that there are some classes of warnings that are
worth enabling during development, but where silencing those
warnings causes code bloat that is not necessary in an optimized
build.  The code bloat to silence the warnings is only enabled
by -Dlint.  Follow the lead of coreutils in setting up -Dlint
whenever full warnings are requested.

* m4/virt-compile-warnings.m4 (LIBVIRT_COMPILE_WARNINGS): Add
-Dlint, and move _FORTIFY_SOURCE to config.h instead of CFLAGS.

diff --git a/m4/virt-compile-warnings.m4 b/m4/virt-compile-warnings.m4
index ba388aad117e42d608310fca368d3fc6a026774e..3a428c32bf957abbed17545ebb9d660f9e614a1d 100644 (file)
--- a/m4/virt-compile-warnings.m4
+++ b/m4/virt-compile-warnings.m4
@@ -100,8 +100,13 @@ AC_DEFUN([LIBVIRT_COMPILE_WARNINGS],[
         gl_WARN_ADD([-Wframe-larger-than=4096])
         dnl gl_WARN_ADD([-Wframe-larger-than=256])
 
+        # Silence certain warnings in gnulib, and use improved glibc headers
+        AC_DEFINE([lint], [1],
+          [Define to 1 if the compiler is checking for lint.])
+        AC_DEFINE([_FORTIFY_SOURCE], [2],
+          [enable compile-time and run-time bounds-checking, and some warnings])
+
         # Extra special flags
-        gl_WARN_ADD([-Wp,-D_FORTIFY_SOURCE=2])
         dnl -fstack-protector stuff passes gl_WARN_ADD with gcc
         dnl on Mingw32, but fails when actually used
         case $host in