On 12/18/2012 03:47 PM, Jakub Jelinek wrote: > On Tue, Dec 18, 2012 at 03:41:58PM +0100, Christian Bruel wrote: >> Canadian Cross Builds fail to build libgcc/unwind-dw2.c >> >> ... >> ../../../../libgcc/unwind-dw2.c:42:21: fatal error: sys/sdt.h: No such >> file or directory >> ... >> >> when the build machine has sys/sdt.h installed (systemtap-sdt-devel), >> but not the target's, because of this: >> >> #ifdef HAVE_SYS_SDT_H >> #include <sys/sdt.h> >> #endif >> >> This appears to be because auto-host.h unconditionally defines >> HAVE_SYS_SDT_H from config.in, that should be guarded with #ifndef >> USED_FOR_TARGET >> >> This patch changes the sys/sdt.h detection to the standard macro to >> correctly generate it. And need to regenerate configure and config.in. >> >> Checked for x86 native boostrap OK and SH4-linux Cross and Native builds >> on host (with and without systemtap host header installed) >> >> OK for trunk ? > > That doesn't look like a correct fix. If HAVE_SYS_SDT_H define is always > guarded with #ifndef USED_FOR_TARGET, then it will never be used in the > target unwind-dw2.c where it is supposed to be used if available. > The configury snippet was clearly looking for target sys/sdt.h header: > if test -f $target_header_dir/sys/sdt.h; then > have_sys_sdt_h=yes >
Well, it should be used by unwind-dw2.c, because we have #include "tconfig.h" that includes it: #ifndef GCC_TCONFIG_H #define GCC_TCONFIG_H #ifndef USED_FOR_TARGET # define USED_FOR_TARGET #endif #include "auto-host.h" in which there is : #ifndef USED_FOR_TARGET #define HAVE_SYS_SDT_H 1 #endif So HAVE_SYS_SDT will be defined in unwind-dw2.c on system that need it. > so the question is why it found a host header instead in your case. This is for everyone. The auto-host.h is used commonly for the target, unded the definition of 'USED_FOR_TARGET' Cheers Christian > > Jakub >
