Fix bugs found by -Wconstant-conversion improvements currently under review.

Specifically, using a an integer outside [0, 1] as a boolean constant seems to
be an easy mistake to make with things like "x == a || b" where the author
intended "x == a || x == b".

The bug caused by calling SkipUntil with three token kinds was also identified
by a VC diagnostic & reported by Francois Pichet as review feedback for my
commit r154163. I've included test cases to verify the error recovery that was
broken/poorly implemented due to this bug.

The other fix (lib/Sema/SemaExpr.cpp) seems like that code was never actually
reached in any of Clang's tests & is related to Objective C features I'm not
familiar with, so I've not been able to construct a test case for it. Perhaps
someone else can.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154325 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 19 insertions, 24 deletions

diff --git a/lib/Parse/ParseTemplate.cpp b/lib/Parse/ParseTemplate.cpp
index 9d5c62567e..61cd9f2119 100644
--- a/lib/Parse/ParseTemplate.cpp
+++ b/lib/Parse/ParseTemplate.cpp
@@ -309,18 +309,19 @@ bool Parser::ParseTemplateParameters(unsigned Depth,
   LAngleLoc = ConsumeToken();
 
   // Try to parse the template parameter list.
-  if (Tok.is(tok::greater))
+  bool Failed = false;
+  if (!Tok.is(tok::greater) && !Tok.is(tok::greatergreater))
+    Failed = ParseTemplateParameterList(Depth, TemplateParams);
+
+  if (Tok.is(tok::greatergreater)) {
+    Tok.setKind(tok::greater);
+    RAngleLoc = Tok.getLocation();
+    Tok.setLocation(Tok.getLocation().getLocWithOffset(1));
+  } else if (Tok.is(tok::greater))
     RAngleLoc = ConsumeToken();
-  else if (ParseTemplateParameterList(Depth, TemplateParams)) {
-    if (Tok.is(tok::greatergreater)) {
-      Tok.setKind(tok::greater);
-      Tok.setLocation(Tok.getLocation().getLocWithOffset(1));
-    } else if (Tok.is(tok::greater))
-      RAngleLoc = ConsumeToken();
-    else {
-      Diag(Tok.getLocation(), diag::err_expected_greater);
-      return true;
-    }
+  else if (Failed) {
+    Diag(Tok.getLocation(), diag::err_expected_greater);
+    return true;
   }
   return false;
 }
@@ -356,10 +357,8 @@ Parser::ParseTemplateParameterList(unsigned Depth,
       // Somebody probably forgot to close the template. Skip ahead and
       // try to get out of the expression. This error is currently
       // subsumed by whatever goes on in ParseTemplateParameter.
-      // TODO: This could match >>, and it would be nice to avoid those
-      // silly errors with template <vec<T>>.
       Diag(Tok.getLocation(), diag::err_expected_comma_greater);
-      SkipUntil(tok::greater, true, true);
+      SkipUntil(tok::comma, tok::greater, tok::greatergreater, true, true);
       return false;
     }
   }
@@ -607,10 +606,7 @@ Parser::ParseTemplateTemplateParameter(unsigned Depth, unsigned Position) {
     if (DefaultArg.isInvalid()) {
       Diag(Tok.getLocation(), 
            diag::err_default_template_template_parameter_not_template);
-      static const tok::TokenKind EndToks[] = { 
-        tok::comma, tok::greater, tok::greatergreater
-      };
-      SkipUntil(EndToks, 3, true, true);
+      SkipUntil(tok::comma, tok::greater, tok::greatergreater, true, true);
     }
   }
   
diff --git a/lib/Parse/ParseTentative.cpp b/lib/Parse/ParseTentative.cpp
index 73501e58ca..b650169b25 100644
--- a/lib/Parse/ParseTentative.cpp
+++ b/lib/Parse/ParseTentative.cpp
@@ -1268,8 +1268,8 @@ Parser::TPResult Parser::TryParseParameterDeclarationClause() {
     if (Tok.is(tok::equal)) {
       // '=' assignment-expression
       // Parse through assignment-expression.
-      tok::TokenKind StopToks[2] ={ tok::comma, tok::r_paren };
-      if (!SkipUntil(StopToks, 2, true/*StopAtSemi*/, true/*DontConsume*/))
+      if (!SkipUntil(tok::comma, tok::r_paren, true/*StopAtSemi*/,
+                     true/*DontConsume*/))
         return TPResult::Error();
     }
 
diff --git a/lib/Parse/Parser.cpp b/lib/Parse/Parser.cpp
index 2c6dff35b2..bc515cab5d 100644
--- a/lib/Parse/Parser.cpp
+++ b/lib/Parse/Parser.cpp
@@ -213,15 +213,14 @@ bool Parser::ExpectAndConsumeSemi(unsigned DiagID) {
 ///
 /// If SkipUntil finds the specified token, it returns true, otherwise it
 /// returns false.
-bool Parser::SkipUntil(const tok::TokenKind *Toks, unsigned NumToks,
-                       bool StopAtSemi, bool DontConsume,
-                       bool StopAtCodeCompletion) {
+bool Parser::SkipUntil(ArrayRef<tok::TokenKind> Toks, bool StopAtSemi,
+                       bool DontConsume, bool StopAtCodeCompletion) {
   // We always want this function to skip at least one token if the first token
   // isn't T and if not at EOF.
   bool isFirstTokenSkipped = true;
   while (1) {
     // If we found one of the tokens, stop and return true.
-    for (unsigned i = 0; i != NumToks; ++i) {
+    for (unsigned i = 0, NumToks = Toks.size(); i != NumToks; ++i) {
       if (Tok.is(Toks[i])) {
         if (DontConsume) {
           // Noop, don't consume the token.