Fixed Sema::CheckEqualityOperands() and Sema::CheckRelationalOperands() to deal more

thoughtfully with incompatible pointers. This includes:

- Emit a diagnostic when two pointers aren't compatible!
- Promote one of the pointers/integers so we maintain the invariant expected by the 
code generator (i.e. that the left/right types match).
- Upgrade the pointer/integer comparison diagnostic to include the types. 

llvm-svn: 41127

1 files changed, 18 insertions, 0 deletions

diff --git a/clang/test/Parser/pointer_promotion.c b/clang/test/Parser/pointer_promotion.c
new file mode 100644
index 00000000000..18cd9687b70
--- /dev/null
+++ b/clang/test/Parser/pointer_promotion.c
@@ -0,0 +1,18 @@
+// RUN: clang -parse-ast-check %s
+
+int test() {
+  void *vp;
+  int *ip;
+  char *cp;
+  struct foo *fp;
+  struct bar *bp;
+  short sint = 7;
+
+  if (ip < cp) ; // expected-warning {{comparison of distinct pointer types ('int *' and 'char *')}}
+  if (cp < fp) ; // expected-warning {{comparison of distinct pointer types ('char *' and 'struct foo *')}}
+  if (fp < bp) ; // expected-warning {{comparison of distinct pointer types ('struct foo *' and 'struct bar *')}}
+  if (ip < 7) ; // expected-warning {{comparison between pointer and integer ('int *' and 'int')}}
+  if (sint < ip) ; // expected-warning {{comparison between pointer and integer ('int' and 'int *')}}
+  if (ip == cp) ; // expected-warning {{comparison of distinct pointer types ('int *' and 'char *')}}
+}
+