From: Jakub Jelinek <jakub@redhat.com>
Date: Tue, 30 May 2017 07:31:03 +0000 (+0200)
Subject: backport: re PR c++/77722 (-fsanitize=undefined doesn't give runtime error in functio... 
X-Git-Tag: releases/gcc-5.5.0~296
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b8ea0a3858e7c22d7cff7f622f525c9124444cae;p=thirdparty%2Fgcc.git

backport: re PR c++/77722 (-fsanitize=undefined doesn't give runtime error in function without return value, unless at least 2 instructions)

	Backported from mainline
	2016-09-27  Jakub Jelinek  <jakub@redhat.com>

	PR c++/77722
	* cp-gimplify.c (cp_ubsan_maybe_instrument_return): Instrument also
	functions that have just a STATEMENT_LIST instead of BIND_EXPR, or
	BIND_EXPR with some statement rather than STATEMENT_LIST as body.

	* g++.dg/ubsan/return-4.C: New test.
	* g++.dg/ubsan/return-5.C: New test.
	* g++.dg/ubsan/return-6.C: New test.

From-SVN: r248614
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 7770101444ea..9a2f36cc6441 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,6 +1,13 @@
 2017-05-30  Jakub Jelinek  <jakub@redhat.com>
 
 	Backported from mainline
+	2016-09-27  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/77722
+	* cp-gimplify.c (cp_ubsan_maybe_instrument_return): Instrument also
+	functions that have just a STATEMENT_LIST instead of BIND_EXPR, or
+	BIND_EXPR with some statement rather than STATEMENT_LIST as body.
+
 	2016-09-20  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/77637
diff --git a/gcc/cp/cp-gimplify.c b/gcc/cp/cp-gimplify.c
index 41b34185425f..b948c536d3f0 100644
--- a/gcc/cp/cp-gimplify.c
+++ b/gcc/cp/cp-gimplify.c
@@ -1337,14 +1337,11 @@ cp_ubsan_maybe_instrument_return (tree fndecl)
     }
   if (t == NULL_TREE)
     return;
-  t = DECL_SAVED_TREE (fndecl);
-  if (TREE_CODE (t) == BIND_EXPR
-      && TREE_CODE (BIND_EXPR_BODY (t)) == STATEMENT_LIST)
-    {
-      tree_stmt_iterator i = tsi_last (BIND_EXPR_BODY (t));
-      t = ubsan_instrument_return (DECL_SOURCE_LOCATION (fndecl));
-      tsi_link_after (&i, t, TSI_NEW_STMT);
-    }
+  tree *p = &DECL_SAVED_TREE (fndecl);
+  if (TREE_CODE (*p) == BIND_EXPR)
+    p = &BIND_EXPR_BODY (*p);
+  t = ubsan_instrument_return (DECL_SOURCE_LOCATION (fndecl));
+  append_to_statement_list (t, p);
 }
 
 void
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 092fd3c709a3..41937cdaee43 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -3,6 +3,11 @@
 	Backported from mainline
 	2016-09-27  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c++/77722
+	* g++.dg/ubsan/return-4.C: New test.
+	* g++.dg/ubsan/return-5.C: New test.
+	* g++.dg/ubsan/return-6.C: New test.
+
 	PR fortran/77666
 	* gfortran.dg/gomp/pr77666.f90: New test.
 
diff --git a/gcc/testsuite/g++.dg/ubsan/return-4.C b/gcc/testsuite/g++.dg/ubsan/return-4.C
new file mode 100644
index 000000000000..d30eef8e31fe
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ubsan/return-4.C
@@ -0,0 +1,18 @@
+// PR c++/77722
+// { dg-do run }
+// { dg-options "-fsanitize=return -w" }
+// { dg-shouldfail "ubsan" }
+
+int
+foo ()
+{
+}
+
+int
+main ()
+{
+  foo ();
+  return 0;
+}
+
+// { dg-output "execution reached the end of a value-returning function without returning a value" }
diff --git a/gcc/testsuite/g++.dg/ubsan/return-5.C b/gcc/testsuite/g++.dg/ubsan/return-5.C
new file mode 100644
index 000000000000..2956c33a0945
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ubsan/return-5.C
@@ -0,0 +1,19 @@
+// PR c++/77722
+// { dg-do run }
+// { dg-options "-fsanitize=return -w" }
+// { dg-shouldfail "ubsan" }
+
+int
+foo ()
+{
+  int a = 5;
+}
+
+int
+main ()
+{
+  foo ();
+  return 0;
+}
+
+// { dg-output "execution reached the end of a value-returning function without returning a value" }
diff --git a/gcc/testsuite/g++.dg/ubsan/return-6.C b/gcc/testsuite/g++.dg/ubsan/return-6.C
new file mode 100644
index 000000000000..0c1e7921c811
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ubsan/return-6.C
@@ -0,0 +1,20 @@
+// PR c++/77722
+// { dg-do run }
+// { dg-options "-fsanitize=return -w" }
+// { dg-shouldfail "ubsan" }
+
+int
+foo ()
+{
+  int a = 5;
+  int b = 5;
+}
+
+int
+main ()
+{
+  foo ();
+  return 0;
+}
+
+// { dg-output "execution reached the end of a value-returning function without returning a value" }