[Parser] Update CachedTokens while parsing ObjectiveC template argument list
Consider the following ObjC++ snippet:
--
@protocol PA;
@protocol PB;
@class NSArray<ObjectType>;
typedef int some_t;
id<PA> FA(NSArray<id<PB>> *h, some_t group);
--
This would hit an assertion in the parser after generating an annotation token
while trying to update the token cache:
Assertion failed: (CachedTokens[CachedLexPos-1].getLastLoc() == Tok.getAnnotationEndLoc() && "The annotation should be until the most recent cached token")
...
7 clang::Preprocessor::AnnotatePreviousCachedTokens(clang::Token const&) + 494
8 clang::Parser::TryAnnotateTypeOrScopeTokenAfterScopeSpec(bool, bool, clang::CXXScopeSpec&, bool) + 1163
9 clang::Parser::TryAnnotateTypeOrScopeToken(bool, bool) + 361
10 clang::Parser::isCXXDeclarationSpecifier(clang::Parser::TPResult, bool*) + 598
...
The cached preprocessor token in this case is:
greatergreater '>>' Loc=<testcase.mm:7:24>
while the annotation ("NSArray<id<PB>>") ends at "testcase.mm:7:25", hence the
assertion.
Properly update the CachedTokens during template parsing to contain
two greater tokens instead of a greatergreater.
Differential Revision: http://reviews.llvm.org/D15173
rdar://problem/23494277
llvm-svn: 259311
diff --git a/clang/lib/Parse/ParseTemplate.cpp b/clang/lib/Parse/ParseTemplate.cpp
index fffc40e..9e68c4a 100644
--- a/clang/lib/Parse/ParseTemplate.cpp
+++ b/clang/lib/Parse/ParseTemplate.cpp
@@ -831,6 +831,7 @@
}
// Strip the initial '>' from the token.
+ Token PrevTok = Tok;
if (RemainingToken == tok::equal && Next.is(tok::equal) &&
areTokensAdjacent(Tok, Next)) {
// Join two adjacent '=' tokens into one, for cases like:
@@ -847,6 +848,17 @@
PP.getSourceManager(),
getLangOpts()));
+ // The advance from '>>' to '>' in a ObjectiveC template argument list needs
+ // to be properly reflected in the token cache to allow correct interaction
+ // between annotation and backtracking.
+ if (ObjCGenericList && PrevTok.getKind() == tok::greatergreater &&
+ RemainingToken == tok::greater && PP.IsPreviousCachedToken(PrevTok)) {
+ PrevTok.setKind(RemainingToken);
+ PrevTok.setLength(1);
+ Token NewToks[] = {PrevTok, Tok};
+ PP.ReplacePreviousCachedToken(NewToks);
+ }
+
if (!ConsumeLastToken) {
// Since we're not supposed to consume the '>' token, we need to push
// this token and revert the current token back to the '>'.