[PATCH] asan: Fix up error recovery for too large frames [PR107317]

[Jakub Jelinek <jakub@redhat.com>]

Hi!

asan_emit_stack_protection and functions it calls have various asserts that
verify sanity of the stack protection instrumentation.  But, that
verification can easily fail if we've diagnosed a frame offset overflow.
asan_emit_stack_protection just emits some extra code in the prologue,
if we've reported errors, we aren't producing assembly, so it doesn't
really matter if we don't include the protection code, compilation
is going to fail anyway.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2022-11-24  Jakub Jelinek  <jakub@redhat.com>

	PR middle-end/107317
	* asan.cc: Include diagnostic-core.h.
	(asan_emit_stack_protection): Return NULL early if seen_error ().

	* gcc.dg/asan/pr107317.c: New test.

--- gcc/asan.cc.jj	2022-06-28 13:03:30.613693889 +0200
+++ gcc/asan.cc	2022-11-23 17:47:09.130332461 +0100
@@ -64,6 +64,7 @@ along with GCC; see the file COPYING3.
 #include "tree-inline.h"
 #include "tree-ssa.h"
 #include "tree-eh.h"
+#include "diagnostic-core.h"
 
 /* AddressSanitizer finds out-of-bounds and use-after-free bugs
    with <2x slowdown on average.
@@ -1818,6 +1819,11 @@ asan_emit_stack_protection (rtx base, rt
   tree str_cst, decl, id;
   int use_after_return_class = -1;
 
+  /* Don't emit anything when doing error recovery, the assertions
+     might fail e.g. if a function had a frame offset overflow.  */
+  if (seen_error ())
+    return NULL;
+
   if (shadow_ptr_types[0] == NULL_TREE)
     asan_init_shadow_ptr_types ();
 
--- gcc/testsuite/gcc.dg/asan/pr107317.c.jj	2022-11-23 17:46:09.145219960 +0100
+++ gcc/testsuite/gcc.dg/asan/pr107317.c	2022-11-23 17:49:45.148024097 +0100
@@ -0,0 +1,13 @@
+/* PR middle-end/107317 */
+/* { dg-do compile { target ilp32 } } */
+/* { dg-options "-fsanitize=address -ffat-lto-objects" } */
+
+void bar (float *, float *);
+
+void
+foo (void)		/* { dg-error "exceeds maximum" } */
+{
+  float a[400000000];
+  float b[200000000];
+  bar (a, b);
+}

	Jakub