[llvm-commits] [PATCH] Fix Alias Bug

[David Greene]

Use a union to do type punning instead of a cast.  A cast
breaks strict aliasing rules.
---
 llvm/unittests/Support/YAMLIOTest.cpp |   10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/llvm/unittests/Support/YAMLIOTest.cpp b/llvm/unittests/Support/YAMLIOTest.cpp
index afa71cc..f148c8d 100644
--- a/llvm/unittests/Support/YAMLIOTest.cpp
+++ b/llvm/unittests/Support/YAMLIOTest.cpp
@@ -783,10 +783,16 @@ namespace yaml {
     static void mapping(IO &io, KindAndFlags& kf) {
       io.mapRequired("kind",  kf.kind);
       // type of flags field varies depending on kind field
+      union {
+        uint32_t i;
+        AFlags aflags;
+        BFlags bflags;
+      } flags = { kf.flags };
+
       if ( kf.kind == kindA )
-        io.mapRequired("flags", *((AFlags*)&kf.flags));
+        io.mapRequired("flags", flags.aflags);
       else
-        io.mapRequired("flags", *((BFlags*)&kf.flags));
+        io.mapRequired("flags", flags.bflags);
     }
   };
 }
-- 
1.7.8.4