Experimentally move the tautological comparison warnings from -Wsign-compare
to -Wtautological-compare.  This implies that they're now on by default.
If this causes chaos, I'll figure something else out.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@112877 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td
index f6fb79d..d46e9a7 100644
--- a/include/clang/Basic/DiagnosticGroups.td
+++ b/include/clang/Basic/DiagnosticGroups.td
@@ -100,6 +100,7 @@
 def : DiagGroup<"stack-protector">;
 def : DiagGroup<"switch-default">;
 def : DiagGroup<"synth">;
+def TautologicalCompare : DiagGroup<"tautological-compare">;
 
 // Preprocessor warnings.
 def : DiagGroup<"builtin-macro-redefined">;
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index d3fdb80..081190b 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2198,10 +2198,10 @@
   InGroup<SignCompare>, DefaultIgnore;
 def warn_lunsigned_always_true_comparison : Warning<
   "comparison of unsigned expression %0 is always %1">,
-  InGroup<SignCompare>, DefaultIgnore;
+  InGroup<TautologicalCompare>;
 def warn_runsigned_always_true_comparison : Warning<
   "comparison of %0 unsigned expression is always %1">,
-  InGroup<SignCompare>, DefaultIgnore;
+  InGroup<TautologicalCompare>;
 
 def err_invalid_this_use : Error<
   "invalid use of 'this' outside of a nonstatic member function">;
@@ -3062,7 +3062,7 @@
 // Array comparisons have similar warnings
 def warn_comparison_always : Warning<
   "%select{self-|array }0comparison always evaluates to %select{false|true|a constant}1">,
-  InGroup<DiagGroup<"tautological-compare">>;
+  InGroup<TautologicalCompare>;
 
 def warn_stringcompare : Warning<
   "result of comparison against %select{a string literal|@encode}0 is "
diff --git a/test/Analysis/additive-folding.c b/test/Analysis/additive-folding.c
index e4a5651..713f788 100644
--- a/test/Analysis/additive-folding.c
+++ b/test/Analysis/additive-folding.c
@@ -183,14 +183,14 @@
 
 void tautologyGE (unsigned a) {
   char* b = malloc(1);
-  if (a >= 0)
+  if (a >= 0) // expected-warning{{always true}}
     free(b);
   return; // no-warning
 }
 
 void tautologyLT (unsigned a) {
   char* b = malloc(1);
-  if (a < 0)
+  if (a < 0) // expected-warning{{always false}}
     return; // expected-warning{{never executed}}
   free(b);
 }
diff --git a/test/Analysis/null-deref-ps.c b/test/Analysis/null-deref-ps.c
index 8daa845..d4d18b4 100644
--- a/test/Analysis/null-deref-ps.c
+++ b/test/Analysis/null-deref-ps.c
@@ -237,7 +237,7 @@
 // Test case from <rdar://problem/6407949>
 void f11(unsigned i) {
   int *x = 0;
-  if (i >= 0) {
+  if (i >= 0) { // expected-warning{{always true}}
     // always true
   } else {
     *x = 42; // no-warning