From: Martin Liska <mliska@suse.cz>
Date: Wed, 25 Apr 2018 07:40:27 +0000 (+0200)
Subject: Backport r259265
X-Git-Tag: releases/gcc-6.5.0~355
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6ba0955f109f289be2f26445d3e81a10396f3ec0;p=thirdparty%2Fgcc.git

Backport r259265

2018-04-25  Martin Liska  <mliska@suse.cz>

	Backport from mainline
	2018-04-10  Richard Biener  <rguenther@suse.de>
		    Martin Liska  <mliska@suse.cz>

	PR lto/85248
	* lto-symtab.c (lto_symtab_merge_p): Handle noreturn attribute.
2018-04-25  Martin Liska  <mliska@suse.cz>

	Backport from mainline
	2018-04-10  Jakub Jelinek  <jakub@redhat.com>

	PR lto/85248
	* gcc.dg/lto/pr85248_0.c: New test.
	* gcc.dg/lto/pr85248_1.c: New test.

From-SVN: r259631
---

diff --git a/gcc/lto/ChangeLog b/gcc/lto/ChangeLog
index c755b383d6d9..c7ee40438b34 100644
--- a/gcc/lto/ChangeLog
+++ b/gcc/lto/ChangeLog
@@ -1,3 +1,12 @@
+2018-04-25  Martin Liska  <mliska@suse.cz>
+
+	Backport from mainline
+	2018-04-10  Richard Biener  <rguenther@suse.de>
+		    Martin Liska  <mliska@suse.cz>
+
+	PR lto/85248
+	* lto-symtab.c (lto_symtab_merge_p): Handle noreturn attribute.
+
 2018-03-07  Martin Liska  <mliska@suse.cz>
 
 	Backport from mainline
diff --git a/gcc/lto/lto-symtab.c b/gcc/lto/lto-symtab.c
index 6b3b785b674f..b01288d7587a 100644
--- a/gcc/lto/lto-symtab.c
+++ b/gcc/lto/lto-symtab.c
@@ -568,6 +568,9 @@ lto_symtab_merge_p (tree prevailing, tree decl)
 	  return false;
 	}
     }
+
+  /* FIXME: after MPX is removed, use flags_from_decl_or_type
+     function instead.  PR lto/85248.  */
   if (DECL_ATTRIBUTES (prevailing) != DECL_ATTRIBUTES (decl))
     {
       tree prev_attr = lookup_attribute ("error", DECL_ATTRIBUTES (prevailing));
@@ -595,6 +598,19 @@ lto_symtab_merge_p (tree prevailing, tree decl)
 		     "warning attribute mismatch\n");
 	  return false;
 	}
+
+      prev_attr = lookup_attribute ("noreturn", DECL_ATTRIBUTES (prevailing));
+      attr = lookup_attribute ("noreturn", DECL_ATTRIBUTES (decl));
+      if ((prev_attr == NULL) != (attr == NULL)
+	  || (prev_attr
+	      && TREE_VALUE (TREE_VALUE (prev_attr))
+		 != TREE_VALUE (TREE_VALUE (attr))))
+	{
+          if (symtab->dump_file)
+	    fprintf (symtab->dump_file, "Not merging decls; "
+		     "noreturn attribute mismatch\n");
+	  return false;
+	}
     }
   return true;
 }
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 84ea927b2318..190eccbbbf6f 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,12 @@
+2018-04-25  Martin Liska  <mliska@suse.cz>
+
+	Backport from mainline
+	2018-04-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR lto/85248
+	* gcc.dg/lto/pr85248_0.c: New test.
+	* gcc.dg/lto/pr85248_1.c: New test.
+
 2018-04-24  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	PR fortran/85520
diff --git a/gcc/testsuite/gcc.dg/lto/pr85248_0.c b/gcc/testsuite/gcc.dg/lto/pr85248_0.c
new file mode 100644
index 000000000000..df61ac976a55
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/lto/pr85248_0.c
@@ -0,0 +1,45 @@
+/* PR lto/85248 */
+/* { dg-lto-do run } */
+/* { dg-lto-options { { -flto -O2 } } } */
+
+extern void test_alias (int s, int e) __asm__ (__USER_LABEL_PREFIX__ "test");
+extern void test_noreturn (int s, int e) __asm__ (__USER_LABEL_PREFIX__ "test")
+  __attribute__ ((__noreturn__));
+
+extern inline __attribute__ ((__always_inline__, __gnu_inline__)) void
+test (int s, int e)
+{
+  if (__builtin_constant_p (s) && s != 0)
+    test_noreturn (s, e);
+  else
+    test_alias (s, e);
+}
+
+int
+foo (void)
+{
+  static volatile int a;
+  return a;
+}
+
+static void
+bar (void)
+{
+  test (0, 1);
+  __builtin_exit (0);
+}
+
+static void
+baz ()
+{
+  test (1, 0);
+}
+
+int
+main ()
+{
+  if (foo ())
+    baz ();
+  bar ();
+  __builtin_abort ();
+}
diff --git a/gcc/testsuite/gcc.dg/lto/pr85248_1.c b/gcc/testsuite/gcc.dg/lto/pr85248_1.c
new file mode 100644
index 000000000000..5ce257181fbe
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/lto/pr85248_1.c
@@ -0,0 +1,9 @@
+/* { dg-options "-fno-lto" } */
+
+void
+test (int s, int e)
+{
+  asm volatile ("" : "+g" (s), "+g" (e) : : "memory");
+  if (s)
+    __builtin_abort ();
+}