Support the 'a' scanf length modifier as an extension in C++.

It should not be supported in C++11, since that uses the C99 standard
library, in which 'a' is a format specifier.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147310 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 13 insertions, 0 deletions

diff --git a/test/SemaCXX/format-strings-0x.cpp b/test/SemaCXX/format-strings-0x.cpp
new file mode 100644
index 0000000000..61bdbe188d
--- /dev/null
+++ b/test/SemaCXX/format-strings-0x.cpp
@@ -0,0 +1,13 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -pedantic -std=c++11 %s
+
+extern "C" {
+extern int scanf(const char *restrict, ...);
+extern int printf(const char *restrict, ...);
+}
+
+void f(char **sp, float *fp) {
+  scanf("%as", sp); // expected-warning{{conversion specifies type 'float *' but the argument has type 'char **'}}
+
+  printf("%a", 1.0);
+  scanf("%afoobar", fp);
+}