[cfe-commits] r173097 - in /cfe/trunk: include/clang/Parse/Parser.h include/clang/Sema/Sema.h lib/Parse/ParseObjc.cpp lib/Sema/SemaExprObjC.cpp test/SemaObjC/selector-3.m

[Douglas Gregor]

On Jan 21, 2013, at 2:32 PM, Fariborz Jahanian <fjahanian at apple.com> wrote:

> Author: fjahanian
> Date: Mon Jan 21 16:32:29 2013
> New Revision: 173097
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=173097&view=rev
> Log:
> objectiveC: don't warn when in -Wselector mode and
> an unimplemented selector is consumed by
> "respondsToSelector:". // rdar://12938616
> 
> Modified:
>    cfe/trunk/include/clang/Parse/Parser.h
>    cfe/trunk/include/clang/Sema/Sema.h
>    cfe/trunk/lib/Parse/ParseObjc.cpp
>    cfe/trunk/lib/Sema/SemaExprObjC.cpp
>    cfe/trunk/test/SemaObjC/selector-3.m
> 
> Modified: cfe/trunk/include/clang/Parse/Parser.h
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Parse/Parser.h?rev=173097&r1=173096&r2=173097&view=diff
> ==============================================================================
> --- cfe/trunk/include/clang/Parse/Parser.h (original)
> +++ cfe/trunk/include/clang/Parse/Parser.h Mon Jan 21 16:32:29 2013
> @@ -1410,7 +1410,8 @@
>   ExprResult ParseObjCDictionaryLiteral(SourceLocation AtLoc);
>   ExprResult ParseObjCBoxedExpr(SourceLocation AtLoc);
>   ExprResult ParseObjCEncodeExpression(SourceLocation AtLoc);
> -  ExprResult ParseObjCSelectorExpression(SourceLocation AtLoc);
> +  ExprResult ParseObjCSelectorExpression(SourceLocation AtLoc,
> +                                         bool WarnSelector=true);
>   ExprResult ParseObjCProtocolExpression(SourceLocation AtLoc);
>   bool isSimpleObjCMessageExpression();
>   ExprResult ParseObjCMessageExpression();
> 
> Modified: cfe/trunk/include/clang/Sema/Sema.h
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Sema/Sema.h?rev=173097&r1=173096&r2=173097&view=diff
> ==============================================================================
> --- cfe/trunk/include/clang/Sema/Sema.h (original)
> +++ cfe/trunk/include/clang/Sema/Sema.h Mon Jan 21 16:32:29 2013
> @@ -4280,7 +4280,8 @@
>                                          SourceLocation AtLoc,
>                                          SourceLocation SelLoc,
>                                          SourceLocation LParenLoc,
> -                                         SourceLocation RParenLoc);
> +                                         SourceLocation RParenLoc,
> +                                         bool WarnSelector);
> 
>   /// ParseObjCProtocolExpression - Build protocol expression for \@protocol
>   ExprResult ParseObjCProtocolExpression(IdentifierInfo * ProtocolName,
> 
> Modified: cfe/trunk/lib/Parse/ParseObjc.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Parse/ParseObjc.cpp?rev=173097&r1=173096&r2=173097&view=diff
> ==============================================================================
> --- cfe/trunk/lib/Parse/ParseObjc.cpp (original)
> +++ cfe/trunk/lib/Parse/ParseObjc.cpp Mon Jan 21 16:32:29 2013
> @@ -2425,6 +2425,8 @@
>   ExprVector KeyExprs;
> 
>   if (Tok.is(tok::colon)) {
> +    bool RespondsToSelector =
> +           selIdent && selIdent->isStr("respondsToSelector");
>     while (1) {
>       // Each iteration parses a single keyword argument.
>       KeyIdents.push_back(selIdent);
> @@ -2463,7 +2465,22 @@
>         return ExprError();
>       }
> 
> -      ExprResult Res(ParseAssignmentExpression());
> +      ExprResult Res;
> +      if (RespondsToSelector) {
> +        if (Tok.is(tok::at)) {
> +          // Special handling for 'respondsToSelector:' which must not warn
> +          // on use of @selector expression as its sole argument.
> +          Token AfterAt = GetLookAheadToken(1);
> +          if (AfterAt.isObjCAtKeyword(tok::objc_selector)) {
> +            SourceLocation AtLoc = ConsumeToken();
> +            Res = ParseObjCSelectorExpression(AtLoc, false);
> +          }
> +        }
> +        RespondsToSelector = false;
> +      }
> +      if (!Res.get())
> +        Res = ParseAssignmentExpression();

This won't work if the @selector is parenthesized, e.g.,

	[foo respondsToSelector:(@selector(blah:wibble:))]

Can't we do this with some simple parser state rather than using lookahead?

	- Doug