PR c++/56607

	* typeck.c (cp_build_binary_op): When calling warn_for_div_by_zero,
	pass op1 through maybe_constant_value first.

	* g++.dg/warn/Wdiv-by-zero-2.C: New test.
	* c-c++-common/pr56607.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@196704 138bc75d-0d04-0410-961f-82ee72b054a4

3 files changed, 69 insertions, 0 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f9fb7f63e6a..db0f92ec463 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2013-03-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/56607
+	* g++.dg/warn/Wdiv-by-zero-2.C: New test.
+	* c-c++-common/pr56607.c: New test.
+
 2013-03-16  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/56582
diff --git a/gcc/testsuite/c-c++-common/pr56607.c b/gcc/testsuite/c-c++-common/pr56607.c
new file mode 100644
index 00000000000..d7faa81151a
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr56607.c
@@ -0,0 +1,29 @@
+/* PR c++/56607 */
+/* { dg-do compile { target { { lp64 || ilp32 } || llp64 } } } */
+/* { dg-options "-O2 -Wdiv-by-zero" } */
+
+int
+f1 (void)
+{
+  return 1 / (sizeof (char) - 1);	/* { dg-warning "division by zero" } */
+}
+
+int
+f2 (void)
+{
+  const int x = sizeof (char) - 1;
+  return 1 / x;				/* { dg-warning "division by zero" "" { target c++ } } */
+}
+
+int
+f3 (void)
+{
+  return 1 / (sizeof (int) / 3 - 1);	/* { dg-warning "division by zero" } */
+}
+
+int
+f4 (void)
+{
+  const int x = sizeof (int) / 3 - 1;
+  return 1 / x;				/* { dg-warning "division by zero" "" { target c++ } } */
+}
diff --git a/gcc/testsuite/g++.dg/warn/Wdiv-by-zero-2.C b/gcc/testsuite/g++.dg/warn/Wdiv-by-zero-2.C
new file mode 100644
index 00000000000..d7e226ce0a5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wdiv-by-zero-2.C
@@ -0,0 +1,34 @@
+// PR c++/56607
+// { dg-do compile { target { { lp64 || ilp32 } || llp64 } } }
+// { dg-options "-O2 -Wdiv-by-zero -std=c++11" }
+
+constexpr int sc () { return sizeof (char); }
+constexpr int si () { return sizeof (int); }
+constexpr int zc () { return sc () - 1; }
+constexpr int zi (int d) { return si () / d - 1; }
+
+int
+f1 (void)
+{
+  return 1 / zc ();			// { dg-warning "division by zero" }
+}
+
+int
+f2 (void)
+{
+  constexpr int x = zc ();
+  return 1 / x;				// { dg-warning "division by zero" }
+}
+
+int
+f3 (void)
+{
+  return 1 / zi (3);			// { dg-warning "division by zero" }
+}
+
+int
+f4 (void)
+{
+  constexpr int x = zi (3);
+  return 1 / x;				// { dg-warning "division by zero" }
+}