On Fri, Jun 08, 2012 at 05:38:32PM +0200, Christophe Fergeau wrote: > From: Eric Blake <eblake@xxxxxxxxxx> > > glibc 2.15 (on Fedora 17) coupled with explicit disabling of > optimization during development dies a painful death: > > In file included from /usr/include/limits.h:27:0, > from /usr/lib/gcc/x86_64-redhat-linux/4.7.0/include/limits.h:169,. > from /usr/lib/gcc/x86_64-redhat-linux/4.7.0/include/syslimits.h:7, > from /usr/lib/gcc/x86_64-redhat-linux/4.7.0/include/limits.h:34, > from util/bitmap.c:26: > /usr/include/features.h:314:4: error: #warning _FORTIFY_SOURCE requires compiling with optimization (-O) [-Werror=cpp] > cc1: all warnings being treated as errors > > Work around this by only conditionally defining _FORTIFY_SOURCE, > in the case where glibc can actually use it. The trick is using > AH_VERBATIM instead of AC_DEFINE. > > * m4/libosinfo-compile-warnings.m4 (LIBVIRT_COMPILE_WARNINGS): Squelch > _FORTIFY_SOURCE when needed to avoid glibc #warnings. s/LIBVIRT/LIBOSINFO/ > --- > m4/libosinfo-compile-warnings.m4 | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/m4/libosinfo-compile-warnings.m4 b/m4/libosinfo-compile-warnings.m4 > index 60152f0..508ff80 100644 > --- a/m4/libosinfo-compile-warnings.m4 > +++ b/m4/libosinfo-compile-warnings.m4 > @@ -86,8 +86,13 @@ AC_DEFUN([LIBOSINFO_COMPILE_WARNINGS],[ > gl_WARN_ADD([-Wframe-larger-than=4096]) > > # Use improved glibc headers > - AC_DEFINE([_FORTIFY_SOURCE], [2], > - [enable compile-time and run-time bounds-checking, and some warnings]) > + AH_VERBATIM([FORTIFY_SOURCE], > + [/* Enable compile-time and run-time bounds-checking, and some warnings, > + without upsetting newer glibc. */ > + #if defined __OPTIMIZE__ && __OPTIMIZE__ > + # define _FORTIFY_SOURCE 2 > + #endif > + ]) > > # Extra special flags > dnl -fstack-protector stuff passes gl_WARN_ADD with gcc ACK with the typo fix Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|
