Backport: https://gcc.gnu.org/git/?p=gcc.git;a=commitdiff;h=b44e9be23d38be8997ae64d7509ac22cb4c556d6

$OpenBSD: patch-gcc_config_i386_i386_c,v 1.5 2017/07/19 09:23:16 pascal Exp $
Index: gcc/config/i386/i386.c
--- gcc/config/i386/i386.c.orig
+++ gcc/config/i386/i386.c
@@ -2476,6 +2476,8 @@ struct ix86_frame
   HOST_WIDE_INT reg_save_offset;
   HOST_WIDE_INT sse_reg_save_offset;
 
+  HOST_WIDE_INT local_size;
+
   /* When save_regs_using_mov is set, emit prologue using
      move instead of push instructions.  */
   bool save_regs_using_mov;
@@ -8686,7 +8688,7 @@ function_arg_advance_32 (CUMULATIVE_ARGS *cum, machine
 			 HOST_WIDE_INT words)
 {
   int res = 0;
-  bool error_p = NULL;
+  bool error_p = false;
 
   if (TARGET_IAMCU)
     {
@@ -11396,6 +11398,7 @@ ix86_compute_frame_layout (struct ix86_frame *frame)
   HOST_WIDE_INT size = get_frame_size ();
   HOST_WIDE_INT to_allocate;
 
+  frame->local_size = size;
   frame->nregs = ix86_nsaved_regs ();
   frame->nsseregs = ix86_nsaved_sseregs ();
 
@@ -12838,6 +12841,9 @@ ix86_expand_prologue (void)
 	  RTX_FRAME_RELATED_P (insn) = 1;
 	}
     }
+
+  if (warn_stack_larger_than && frame.local_size > stack_larger_than_size)
+    warning (OPT_Wstack_larger_than_, "stack usage is %lld bytes", frame.local_size);
 
   int_registers_saved = (frame.nregs == 0);
   sse_registers_saved = (frame.nsseregs == 0);
