1 files changed, 12 insertions, 0 deletions
diff --git a/gcc/ira.c b/gcc/ira.c
index 41e05f4..ee6010a 100644
--- a/gcc/ira.c
+++ b/gcc/ira.c
@@ -5532,6 +5532,18 @@ do_reload (void)
   if (need_dce && optimize)
     run_fast_dce ();
 
+  /* Diagnose uses of the hard frame pointer when it is used as a global
+     register.  Often we can get away with letting the user appropriate
+     the frame pointer, but we should let them know when code generation
+     makes that impossible.  */
+  if (global_regs[HARD_FRAME_POINTER_REGNUM] && frame_pointer_needed)
+    {
+      tree decl = global_regs_decl[HARD_FRAME_POINTER_REGNUM];
+      error_at (DECL_SOURCE_LOCATION (current_function_decl),
+                "frame pointer required, but reserved");
+      inform (DECL_SOURCE_LOCATION (decl), "for %qD", decl);
+    }
+
   timevar_pop (TV_IRA);
 }