Promote enum types during -Wsign-compare. Fixes some spurious warnings,

mostly during conditional expressions.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@98975 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 80 insertions, 3 deletions

diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 3fac79deba..522a7c1076 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -2045,6 +2045,11 @@ void Sema::CheckSignCompare(Expr *lex, Expr *rex, SourceLocation OpLoc,
     if (!tmp.isNull()) rt = tmp;
   }
 
+  if (const EnumType *E = lt->getAs<EnumType>())
+    lt = E->getDecl()->getPromotionType();
+  if (const EnumType *E = rt->getAs<EnumType>())
+    rt = E->getDecl()->getPromotionType();
+
   // The rule is that the signed operand becomes unsigned, so isolate the
   // signed operand.
   Expr *signedOperand = lex, *unsignedOperand = rex;
diff --git a/test/SemaCXX/conditional-expr.cpp b/test/SemaCXX/conditional-expr.cpp
index 4fcb0bb98d..accc8db6c4 100644
--- a/test/SemaCXX/conditional-expr.cpp
+++ b/test/SemaCXX/conditional-expr.cpp
@@ -154,8 +154,8 @@ void test()
   i1 = i1 ? i1 : ir1;
   int *pi1 = i1 ? &i1 : 0;
   pi1 = i1 ? 0 : &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}} ??
+  i1 = i1 ? i1 : EVal;
+  i1 = i1 ? EVal : i1;
   d1 = i1 ? 'c' : 4.0;
   d1 = i1 ? 4.0 : 'c';
   Base *pb = i1 ? (Base*)0 : (Derived*)0;
@@ -191,7 +191,7 @@ void test()
   test0 = test0 ? (short) 10 : test0;
 
   test0 = test0 ? EVal : test0;
-  test0 = test0 ? EVal : (int) test0; // expected-warning {{operands of ? are integers of different signs}}
+  test0 = test0 ? EVal : (int) test0;
 
   // Note the thing that this does not test: since DR446, various situations
   // *must* create a separate temporary copy of class objects. This can only
diff --git a/test/SemaCXX/warn-sign-compare.cpp b/test/SemaCXX/warn-sign-compare.cpp
new file mode 100644
index 0000000000..3042bfde6e
--- /dev/null
+++ b/test/SemaCXX/warn-sign-compare.cpp
@@ -0,0 +1,72 @@
+// RUN: %clang_cc1 -verify -fsyntax-only -Wsign-compare %s
+
+// NOTE: When a 'enumeral mismatch' warning is implemented then expect several
+// of the following cases to be impacted.
+
+// namespace for anonymous enums tests
+namespace test1 {
+  enum { A };
+  enum { B = -1 };
+
+  template <typename T> struct Foo {
+    enum { C };
+    enum { D = ~0U };
+  };
+
+  enum { E = ~0U };
+
+  void doit_anonymous( int i ) {
+    int a1 = 1 ? i : A;
+    int a2 = 1 ? A : i;
+
+    int b1 = 1 ? i : B;
+    int b2 = 1 ? B : i;
+
+    int c1 = 1 ? i : Foo<bool>::C;
+    int c2 = 1 ? Foo<bool>::C : i;
+
+    int d1 = 1 ? i : Foo<bool>::D; // expected-warning {{operands of ? are integers of different signs}}
+    int d2 = 1 ? Foo<bool>::D : i; // expected-warning {{operands of ? are integers of different signs}}
+    int d3 = 1 ? B : Foo<bool>::D; // expected-warning {{operands of ? are integers of different signs}}
+    int d4 = 1 ? Foo<bool>::D : B; // expected-warning {{operands of ? are integers of different signs}}
+
+    int e1 = 1 ? i : E; // expected-warning {{operands of ? are integers of different signs}}
+    int e2 = 1 ? E : i; // expected-warning {{operands of ? are integers of different signs}}
+    int e3 = 1 ? E : B; // expected-warning {{operands of ? are integers of different signs}}
+    int e4 = 1 ? B : E; // expected-warning {{operands of ? are integers of different signs}}
+  }
+}
+
+// namespace for named enums tests
+namespace test2 {
+  enum Named1 { A };
+  enum Named2 { B = -1 };
+
+  template <typename T> struct Foo {
+    enum Named3 { C };
+    enum Named4 { D = ~0U };
+  };
+
+  enum Named5 { E = ~0U };
+
+  void doit_anonymous( int i ) {
+    int a1 = 1 ? i : A;
+    int a2 = 1 ? A : i;
+
+    int b1 = 1 ? i : B;
+    int b2 = 1 ? B : i;
+
+    int c1 = 1 ? i : Foo<bool>::C;
+    int c2 = 1 ? Foo<bool>::C : i;
+
+    int d1 = 1 ? i : Foo<bool>::D; // expected-warning {{operands of ? are integers of different signs}}
+    int d2 = 1 ? Foo<bool>::D : i; // expected-warning {{operands of ? are integers of different signs}}
+    int d3 = 1 ? B : Foo<bool>::D; // expected-warning {{operands of ? are integers of different signs}}
+    int d4 = 1 ? Foo<bool>::D : B; // expected-warning {{operands of ? are integers of different signs}}
+
+    int e1 = 1 ? i : E; // expected-warning {{operands of ? are integers of different signs}}
+    int e2 = 1 ? E : i; // expected-warning {{operands of ? are integers of different signs}}
+    int e3 = 1 ? E : B; // expected-warning {{operands of ? are integers of different signs}}
+    int e4 = 1 ? B : E; // expected-warning {{operands of ? are integers of different signs}}
+  }
+}