* builtins.c (fold_builtin_constant_p): Return integer_zero_node

for complex expressions when cfun == 0.
	* doc/extend.texi: Document that __builtin_constant_p can be
used in data initializers as well as functions.
	* gcc.dg/bconstp-1.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@44619 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 25 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/bconstp-1.c b/gcc/testsuite/gcc.dg/bconstp-1.c
new file mode 100644
index 00000000000..36831a5d6d5
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/bconstp-1.c
@@ -0,0 +1,25 @@
+/* { dg-do compile } */
+
+/* This test checks that builtin_constant_p can be used safely in
+   initializers for static data.  The macro X() defined below should
+   be an acceptable initializer expression no matter how complex its
+   argument is.  */
+
+extern int a;
+extern int b;
+
+extern int foo(void);
+extern int bar(void);
+
+#define X(exp) (__builtin_constant_p(exp) ? (exp) : -1)
+
+const short tests[] = {
+  X(0),
+  X(a),
+  X(0 && a),
+  X(a && b),
+  X(foo()),
+  X(0 && foo()),
+  X(a && foo()),
+  X(foo() && bar())
+};