Patch for C++ build on HP-UX and to implement -static-libstdc++

[Steve Ellcey]

I recently discovered that after moving to the C++ bootstrap, the IA64
HP-UX GCC compiler would build and test OK, but if you tried to run the
installed compiler you would get an error about not being able to find
libgcc_s.so.0.

Joseph and Rainer pointed me at definining gcc_cv_ld_static_dynamic,
gcc_cv_ld_static_option, and gcc_cv_ld_dynamic_option in the
configure.ac script and that helped but resulted in a new problem.

In addition to allowing GCC to link with the static libgcc and libstdc++
these changes resulted in GCC trying to link in a static libunwind.
On IA64 HP-UX we use the system libunwind and it only comes in a shared
version.  So my solution was to change gcc.c so that we only link in the
archive libunwind if we are not using the system libunwind.  I did this by
having unwind_ipinfo.m4 set a new macro (USE_SYSTEM_LIBUNWIND) when
we are using the system libunwind and then checking for this in
gcc.c.

I am not sure if any other platforms use the system libunwind and if
this will cause them problem, IA64 HP-UX is the only platform to use the
system libunwind by default and I'd rather not invent a new config flag
to handle the static vs. dynamic libunwind issue unless we need to.

In addition to this problem on IA64 I found that the 32 bit PA compiler
was not building (due to a problem with not finding libgcc_s) and that
the 64 bit PA compiler was not handling -static-libstdc.  This patch
fixes those problems as well with the change to configure.ac.

Hopefully, there is no issue with the configure.ac change, but I would
like some feedback on the unwind_ipinfo.m4 and gcc.c changes for
USE_SYSTEM_LIBUNWIND.  I don't know if there is a better way to handle
this or not.

Tested on IA64 HP-UX and Linux and on 32 and 64 bit PA.

OK for checkin?

Steve Ellcey
sje@cup.hp.com


config/ChangeLog

2011-07-28  Steve Ellcey  <sje@cup.hp.com>

	* unwind_ipinfo.m4 (USE_SYSTEM_LIBUNWIND): Define.


gcc/ChangeLog


2011-07-28  Steve Ellcey  <sje@cup.hp.com>

	* configure.ac (gcc_cv_ld_static_dynamic): Define for *-*-hpux*.
	(gcc_cv_ld_static_option): Ditto.
	(gcc_cv_ld_dynamic_option): Ditto.
	* gcc.c (init_spec): Use USE_SYSTEM_LIBUNWIND.



Index: config/unwind_ipinfo.m4
===================================================================
--- config/unwind_ipinfo.m4	(revision 176899)
+++ config/unwind_ipinfo.m4	(working copy)
@@ -34,4 +34,8 @@
   if test x$have_unwind_getipinfo = xyes; then
     AC_DEFINE(HAVE_GETIPINFO, 1, [Define if _Unwind_GetIPInfo is available.])
   fi
+
+  if test x$with_system_libunwind = xyes; then
+    AC_DEFINE(USE_SYSTEM_LIBUNWIND, 1, [Define if using system unwind library.])
+  fi
 ])
Index: gcc/configure.ac
===================================================================
--- gcc/configure.ac	(revision 176899)
+++ gcc/configure.ac	(working copy)
@@ -3240,6 +3240,13 @@
       *-*-solaris2*)
         gcc_cv_ld_static_dynamic=yes
         ;;
+      *-*-hpux*)
+	if test x"$gnu_ld" = xno; then
+	  gcc_cv_ld_static_dynamic=yes
+	  gcc_cv_ld_static_option="-aarchive"
+	  gcc_cv_ld_dynamic_option="-adefault"
+	fi
+	;;
     esac
   fi
 fi
Index: gcc/gcc.c
===================================================================
--- gcc/gcc.c	(revision 176899)
+++ gcc/gcc.c	(working copy)
@@ -1389,7 +1389,7 @@
 			    "-lgcc",
 			    "-lgcc_eh"
 #ifdef USE_LIBUNWIND_EXCEPTIONS
-# ifdef HAVE_LD_STATIC_DYNAMIC
+# if defined(HAVE_LD_STATIC_DYNAMIC) && !defined(USE_SYSTEM_LIBUNWIND)
 			    " %{!static:" LD_STATIC_OPTION "} -lunwind"
 			    " %{!static:" LD_DYNAMIC_OPTION "}"
 # else