Implement the conditional-operator part of -Wsign-compare. Turn

DiagnoseSignCompare into Sema::CheckSignCompare and call it from more places.

Add some enumerator tests.  These seem to expose some oddities in the
types we're converting C++ enumerators to;  in particular, they're converting
to unsigned before int, which seems to contradict 4.5 [conv.prom] p2.

Note to self: stop baiting Doug in my commit messages.

llvm-svn: 86128

4 files changed, 66 insertions, 2 deletions

diff --git a/clang/test/Sema/compare.c b/clang/test/Sema/compare.c
index 50b40e459c3..9cbbfba935b 100644
--- a/clang/test/Sema/compare.c
+++ b/clang/test/Sema/compare.c
@@ -13,6 +13,18 @@ int ints(long a, unsigned long b) {
          ((short)a == b) + // expected-warning {{comparison of integers of different signs}}
          (a == (unsigned int) b) +  // expected-warning {{comparison of integers of different signs}}
          (a == (unsigned short) b); // expected-warning {{comparison of integers of different signs}}
+
+  enum Enum {B};
+  return (a == B) +
+         ((int)a == B) +
+         ((short)a == B) +
+         (a == (unsigned int) B) +  // expected-warning {{comparison of integers of different signs}}
+         (a == (unsigned short) B); // expected-warning {{comparison of integers of different signs}}         
+
+  // Should be able to prove all of these are non-negative.
+  return (b == (long) B) +
+         (b == (int) B) +
+         (b == (short) B);
 }
 
 int equal(char *a, const char *b) {
diff --git a/clang/test/Sema/conditional-expr.c b/clang/test/Sema/conditional-expr.c
index 1f0a9deb5e4..3bfeae5d4c5 100644
--- a/clang/test/Sema/conditional-expr.c
+++ b/clang/test/Sema/conditional-expr.c
@@ -34,6 +34,25 @@ void foo() {
 
   typedef void *asdf;
   *(0 ? (asdf) 0 : &x) = 10;
+
+  unsigned long test0 = 5;
+  test0 = test0 ? (long) test0 : test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? (int) test0 : test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? (short) test0 : test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? test0 : (long) test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? test0 : (int) test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? test0 : (short) test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? test0 : (long) 10;
+  test0 = test0 ? test0 : (int) 10;
+  test0 = test0 ? test0 : (short) 10;
+  test0 = test0 ? (long) 10 : test0;
+  test0 = test0 ? (int) 10 : test0;
+  test0 = test0 ? (short) 10 : test0;
+
+  enum Enum { EVal };
+  test0 = test0 ? EVal : test0;
+  test0 = test0 ? EVal : (int) test0; // okay: EVal is an int
+  test0 = test0 ? (unsigned) EVal : (int) test0; // expected-warning {{operands of ? are integers of different signs}}
 }
 
 int Postgresql() {
diff --git a/clang/test/SemaCXX/compare.cpp b/clang/test/SemaCXX/compare.cpp
new file mode 100644
index 00000000000..806b078e8df
--- /dev/null
+++ b/clang/test/SemaCXX/compare.cpp
@@ -0,0 +1,15 @@
+// RUN: clang-cc -fsyntax-only -pedantic -verify %s
+
+int test0(long a, unsigned long b) {
+  enum Enum {B};
+  return (a == B) +        // expected-warning {{comparison of integers of different signs}}
+         ((int)a == B) +   // expected-warning {{comparison of integers of different signs}}
+         ((short)a == B) + // expected-warning {{comparison of integers of different signs}}
+         (a == (unsigned int) B) +  // expected-warning {{comparison of integers of different signs}}
+         (a == (unsigned short) B); // expected-warning {{comparison of integers of different signs}}         
+
+  // Should be able to prove all of these are non-negative.
+  return (b == (long) B) +
+         (b == (int) B) +
+         (b == (short) B);
+}
diff --git a/clang/test/SemaCXX/conditional-expr.cpp b/clang/test/SemaCXX/conditional-expr.cpp
index fea3324b5fd..da2dd67d061 100644
--- a/clang/test/SemaCXX/conditional-expr.cpp
+++ b/clang/test/SemaCXX/conditional-expr.cpp
@@ -156,8 +156,8 @@ void test()
   i1 = i1 ? i1 : ir1;
   int *pi1 = i1 ? &i1 : 0;
   pi1 = i1 ? 0 : &i1;
-  i1 = i1 ? i1 : EVal;
-  i1 = i1 ? EVal : i1;
+  i1 = i1 ? i1 : EVal; // expected-warning {{operands of ? are integers of different signs}} ??
+  i1 = i1 ? EVal : i1; // expected-warning {{operands of ? are integers of different signs}} ??
   d1 = i1 ? 'c' : 4.0;
   d1 = i1 ? 4.0 : 'c';
   Base *pb = i1 ? (Base*)0 : (Derived*)0;
@@ -177,6 +177,24 @@ void test()
   (void)&(i1 ? flds.b1 : flds.i1); // expected-error {{address of bit-field requested}}
   (void)&(i1 ? flds.i1 : flds.b1); // expected-error {{address of bit-field requested}}
   
+
+  unsigned long test0 = 5;
+  test0 = test0 ? (long) test0 : test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? (int) test0 : test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? (short) test0 : test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? test0 : (long) test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? test0 : (int) test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? test0 : (short) test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? test0 : (long) 10;
+  test0 = test0 ? test0 : (int) 10;
+  test0 = test0 ? test0 : (short) 10;
+  test0 = test0 ? (long) 10 : test0;
+  test0 = test0 ? (int) 10 : test0;
+  test0 = test0 ? (short) 10 : test0;
+
+  test0 = test0 ? EVal : test0;
+  test0 = test0 ? EVal : (int) test0; // expected-warning {{operands of ? are integers of different signs}}
+
   // Note the thing that this does not test: since DR446, various situations
   // *must* create a separate temporary copy of class objects. This can only
   // be properly tested at runtime, though.