when compiling in a GNU mode (e.g. gnu99) treat VLAs with a size that can be folded to a constant

as constant size arrays.  This has slightly different semantics in some insane cases, but allows
us to accept some constructs that GCC does.  Continue to be pedantic in -std=c99 and other
modes.  This addressed rdar://8733881 - error "variable-sized object may not be initialized"; g++ accepts same code

llvm-svn: 132983

1 files changed, 9 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/c99-variable-length-array.cpp b/clang/test/SemaCXX/c99-variable-length-array.cpp
index 98df1dbfe81..3f1d6a8a55c 100644
--- a/clang/test/SemaCXX/c99-variable-length-array.cpp
+++ b/clang/test/SemaCXX/c99-variable-length-array.cpp
@@ -121,3 +121,12 @@ namespace PR8209 {
     (void)new vla_type; // expected-error{{variably}}
   }
 }
+
+namespace rdar8733881 { // rdar://8733881
+
+static const int k_cVal3 = (int)(1000*0.2f);
+  int f() {
+    // Ok, fold to a constant size array as an extension.
+    char rgch[k_cVal3] = {0};
+  }
+}