Index: sparc-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/sparc-tdep.c,v
retrieving revision 1.156
diff -u -p -r1.156 sparc-tdep.c
--- sparc-tdep.c	21 Nov 2004 20:11:09 -0000	1.156
+++ sparc-tdep.c	23 Nov 2004 05:01:15 -0000
@@ -640,6 +640,17 @@ sparc_frame_cache (struct frame_info *ne
   return cache;
 }
 
+/* Return True if the instruction corresponding to PC is a "unimp"
+   instruction.  */
+
+static int
+is_unimp_insn (CORE_ADDR pc)
+{
+  const unsigned long insn = sparc_fetch_instruction (pc);
+  
+  return ((insn & 0xc1c00000) == 0);
+}
+
 struct sparc_frame_cache *
 sparc32_frame_cache (struct frame_info *next_frame, void **this_cache)
 {
@@ -665,6 +676,21 @@ sparc32_frame_cache (struct frame_info *
 	    cache->struct_return_p = 1;
 	}
     }
+  else
+    {
+      /* There is no debugging information for this function to
+         help us determine whether this function returns a struct
+         or not.  So we rely on another heuristic which is to check
+         the instruction at the return address and see if this is
+         a "unimp" instruction.  If it is, then it is struct-return
+         function.  */
+      CORE_ADDR pc;
+      int regnum = cache->frameless_p ? SPARC_O7_REGNUM : SPARC_I7_REGNUM;
+
+      pc = frame_unwind_register_unsigned (next_frame, regnum) + 8;
+      if (is_unimp_insn (pc))
+        cache->struct_return_p = 1;
+    }
 
   return cache;
 }