Import the setjump/longjump exception handling fixes from GCC 2.95.3.test3

that were removed from GCC 2.95.3.test4 and the subsequent release due
to problems on HP-UX.  However, they work just fine on all the BSD's.

W/o these patches the following program segmentation faults if compiled
with -O2 (but not -Os or -O or -O0):

#include <stdio.h>

class A {
public:
  A() { printf("c'tor A\n"); }
  ~A(){ printf("d'tor A\n"); }
};

class foo : public A {
public:
  foo()  { printf("C'tor foo\n"); throw 8; }
  ~foo() { printf("D'tor foo\n"); }
};

int main(){
  try { foo fii; }
  catch (int){ printf("catch ...\n"); }
  return 0;
}

1 files changed, 12 insertions, 0 deletions

diff --git a/contrib/gcc/varasm.c b/contrib/gcc/varasm.c
index b935065..56fe2ad 100644
--- a/contrib/gcc/varasm.c
+++ b/contrib/gcc/varasm.c
@@ -3494,6 +3494,18 @@ force_const_mem (mode, x)
 
 	  pop_obstacks ();
 	}
+      if (GET_CODE (x) == LABEL_REF)
+	{
+	  extern rtx forced_labels;
+
+	  push_obstacks_nochange ();
+	  rtl_in_saveable_obstack ();
+
+	  forced_labels = gen_rtx_EXPR_LIST (VOIDmode,
+					     XEXP (x, 0),
+					     forced_labels);
+	  pop_obstacks ();
+	}
 
       /* Allocate a pool constant descriptor, fill it in, and chain it in.  */