#  https://gcc.gnu.org/legacy-ml/gcc-patches/2012-12/msg01122.html

Hello,

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 ?

Thanks,

Christian

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Content-Type: text/x-patch; name="cross-sdt.patch"
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment; filename="cross-sdt.patch"

2012-12-18  Christian Bruel  <christian.bruel@st.com>

	* configure.ac: Check sys/sdt.h with AC_CHECK_HEADERS.
	* configure: Regenerate.
	* config.in: Regenerat.e

Index: gcc/configure
===================================================================
--- gcc/configure	(revision 194574)
+++ gcc/configure	(working copy)
@@ -8464,7 +8464,7 @@
 
 for ac_header in limits.h stddef.h string.h strings.h stdlib.h time.h iconv.h \
 		 fcntl.h ftw.h unistd.h sys/file.h sys/time.h sys/mman.h \
-		 sys/resource.h sys/param.h sys/times.h sys/stat.h \
+		 sys/resource.h sys/param.h sys/times.h sys/sdt.h sys/stat.h \
 		 direct.h malloc.h langinfo.h ldfcn.h locale.h wchar.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
@@ -27887,20 +27887,6 @@
 
 fi
 
-# Test for <sys/sdt.h> on the target.
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking sys/sdt.h in the target C library" >&5
-$as_echo_n "checking sys/sdt.h in the target C library... " >&6; }
-have_sys_sdt_h=no
-if test -f $target_header_dir/sys/sdt.h; then
-  have_sys_sdt_h=yes
-
-$as_echo "#define HAVE_SYS_SDT_H 1" >>confdefs.h
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $have_sys_sdt_h" >&5
-$as_echo "$have_sys_sdt_h" >&6; }
-
 # Check if TFmode long double should be used by default or not.
 # Some glibc targets used DFmode long double, but with glibc 2.4
 # and later they can use TFmode.
Index: gcc/config.in
===================================================================
--- gcc/config.in	(revision 194574)
+++ gcc/config.in	(working copy)
@@ -1416,7 +1416,7 @@
 #endif
 
 
-/* Define if your PowerPC64 linker supports a large TOC. */
+/* Define if your AIX linker supports a large TOC. */
 #ifndef USED_FOR_TARGET
 #undef HAVE_LD_LARGE_TOC
 #endif
@@ -1670,8 +1670,11 @@
 #endif
 
 
-/* Define if your target C library provides sys/sdt.h */
+/* Define to 1 if you have the <sys/sdt.h> header file. */
+#ifndef USED_FOR_TARGET
 #undef HAVE_SYS_SDT_H
+#endif
+
 
 /* Define to 1 if you have the <sys/stat.h> header file. */
 #ifndef USED_FOR_TARGET
Index: gcc/configure.ac
===================================================================
--- gcc/configure.ac	(revision 194574)
+++ gcc/configure.ac	(working copy)
@@ -1029,7 +1029,7 @@
 AC_HEADER_TIOCGWINSZ
 AC_CHECK_HEADERS(limits.h stddef.h string.h strings.h stdlib.h time.h iconv.h \
 		 fcntl.h ftw.h unistd.h sys/file.h sys/time.h sys/mman.h \
-		 sys/resource.h sys/param.h sys/times.h sys/stat.h \
+		 sys/resource.h sys/param.h sys/times.h sys/sdt.h sys/stat.h \
 		 direct.h malloc.h langinfo.h ldfcn.h locale.h wchar.h)
 
 # Check for thread headers.
@@ -5326,17 +5326,6 @@
 	    [Define if your target C library provides stack protector support])
 fi
 
-# Test for <sys/sdt.h> on the target.
-GCC_TARGET_TEMPLATE([HAVE_SYS_SDT_H])
-AC_MSG_CHECKING(sys/sdt.h in the target C library)
-have_sys_sdt_h=no
-if test -f $target_header_dir/sys/sdt.h; then
-  have_sys_sdt_h=yes
-  AC_DEFINE(HAVE_SYS_SDT_H, 1,
-            [Define if your target C library provides sys/sdt.h])
-fi
-AC_MSG_RESULT($have_sys_sdt_h)
-
 # Check if TFmode long double should be used by default or not.
 # Some glibc targets used DFmode long double, but with glibc 2.4
 # and later they can use TFmode.