r203693 - Objective-C. Issue diagnostics on mismatched methods when their selector is used

Nico Weber thakis at chromium.org
Wed Mar 26 21:22:07 PDT 2014


Hi,

how does one fix this warning? I have this code:

    NSString* string = @"";
    [NSThread detachNewThreadSelector:@selector(length)
                             toTarget:string
                           withObject:nil];


clang now warns:

../../content/renderer/renderer_main_platform_delegate_mac.mm:122:39:
error: several methods with selector 'length' of mismatched types are found
for the @selector expression [-Werror,-Wselector-type-mismatch]
    [NSThread detachNewThreadSelector:@selector(length)
                                      ^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSString.h:78:1:
note: method 'length' declared here
- (NSUInteger)length;
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSStatusItem.h:45:1:
note: method 'length' declared here
- (CGFloat)length;
^

What am I supposed to do about this?



On Wed, Mar 12, 2014 at 11:34 AM, Fariborz Jahanian <fjahanian at apple.com>wrote:

> Author: fjahanian
> Date: Wed Mar 12 13:34:01 2014
> New Revision: 203693
>
> URL: http://llvm.org/viewvc/llvm-project?rev=203693&view=rev
> Log:
> Objective-C. Issue diagnostics on mismatched methods when their selector
> is used
> in an @selector expression. // rdar://15794055
>
> Modified:
>     cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
>     cfe/trunk/lib/Sema/SemaExprObjC.cpp
>     cfe/trunk/test/SemaObjC/selector-1.m
>
> Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=203693&r1=203692&r2=203693&view=diff
>
> ==============================================================================
> --- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
> +++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Wed Mar 12
> 13:34:01 2014
> @@ -892,7 +892,9 @@ def warn_unimplemented_selector:  Warnin
>    InGroup<Selector>, DefaultIgnore;
>  def warn_unimplemented_protocol_method : Warning<
>    "method %0 in protocol %1 not implemented">, InGroup<Protocol>;
> -
> +def warning_multiple_selectors: Warning<
> +  "several methods with selector %0 of mismatched types are found for the
> @selector expression">,
> +  InGroup<SelectorTypeMismatch>;
>  // C++ declarations
>  def err_static_assert_expression_is_not_constant : Error<
>    "static_assert expression is not an integral constant expression">;
>
> Modified: cfe/trunk/lib/Sema/SemaExprObjC.cpp
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExprObjC.cpp?rev=203693&r1=203692&r2=203693&view=diff
>
> ==============================================================================
> --- cfe/trunk/lib/Sema/SemaExprObjC.cpp (original)
> +++ cfe/trunk/lib/Sema/SemaExprObjC.cpp Wed Mar 12 13:34:01 2014
> @@ -973,6 +973,58 @@ ExprResult Sema::ParseObjCEncodeExpressi
>    return BuildObjCEncodeExpression(AtLoc, TInfo, RParenLoc);
>  }
>
> +static bool HelperToDiagnoseMismatchedMethodsInGlobalPool(Sema &S,
> +                                               SourceLocation AtLoc,
> +                                               ObjCMethodDecl *Method,
> +                                               ObjCMethodList &MethList) {
> +  ObjCMethodList *M = &MethList;
> +  bool Warned = false;
> +  for (M = M->getNext(); M; M=M->getNext()) {
> +    ObjCMethodDecl *MatchingMethodDecl = M->Method;
> +    if (MatchingMethodDecl == Method ||
> +        isa<ObjCImplDecl>(MatchingMethodDecl->getDeclContext()) ||
> +        MatchingMethodDecl->getSelector() != Method->getSelector())
> +      continue;
> +    if (!S.MatchTwoMethodDeclarations(Method,
> +                                      MatchingMethodDecl,
> Sema::MMS_loose)) {
> +      if (!Warned) {
> +        Warned = true;
> +        S.Diag(AtLoc, diag::warning_multiple_selectors)
> +          << Method->getSelector();
> +        S.Diag(Method->getLocation(), diag::note_method_declared_at)
> +          << Method->getDeclName();
> +      }
> +      S.Diag(MatchingMethodDecl->getLocation(),
> diag::note_method_declared_at)
> +        << MatchingMethodDecl->getDeclName();
> +    }
> +  }
> +  return Warned;
> +}
> +
> +static void DiagnoseMismatchedSelectors(Sema &S, SourceLocation AtLoc,
> +                                        ObjCMethodDecl *Method) {
> +  unsigned DIAG = diag::warning_multiple_selectors;
> +  if (S.Diags.getDiagnosticLevel(DIAG, SourceLocation())
> +        == DiagnosticsEngine::Ignored)
> +    return;
> +  bool Warned = false;
> +  for (Sema::GlobalMethodPool::iterator b = S.MethodPool.begin(),
> +       e = S.MethodPool.end(); b != e; b++) {
> +    // first, instance methods
> +    ObjCMethodList &InstMethList = b->second.first;
> +    if (HelperToDiagnoseMismatchedMethodsInGlobalPool(S, AtLoc,
> +                                                      Method,
> InstMethList))
> +      Warned = true;
> +
> +    // second, class methods
> +    ObjCMethodList &ClsMethList = b->second.second;
> +    if (HelperToDiagnoseMismatchedMethodsInGlobalPool(S, AtLoc,
> +                                                      Method,
> ClsMethList) ||
> +        Warned)
> +      return;
> +  }
> +}
> +
>  ExprResult Sema::ParseObjCSelectorExpression(Selector Sel,
>                                               SourceLocation AtLoc,
>                                               SourceLocation SelLoc,
> @@ -994,7 +1046,8 @@ ExprResult Sema::ParseObjCSelectorExpres
>
>      } else
>          Diag(SelLoc, diag::warn_undeclared_selector) << Sel;
> -  }
> +  } else
> +    DiagnoseMismatchedSelectors(*this, AtLoc, Method);
>
>    if (!Method ||
>        Method->getImplementationControl() != ObjCMethodDecl::Optional) {
>
> Modified: cfe/trunk/test/SemaObjC/selector-1.m
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjC/selector-1.m?rev=203693&r1=203692&r2=203693&view=diff
>
> ==============================================================================
> --- cfe/trunk/test/SemaObjC/selector-1.m (original)
> +++ cfe/trunk/test/SemaObjC/selector-1.m Wed Mar 12 13:34:01 2014
> @@ -1,18 +1,17 @@
>  // RUN: %clang_cc1 -verify %s
> -// expected-no-diagnostics
>
>  @interface I
> -- (id) compare: (char) arg1;
> +- (id) compare: (char) arg1; // expected-note {{method 'compare:'
> declared here}}
>  - length;
>  @end
>
>  @interface J
> -- (id) compare: (id) arg1;
> +- (id) compare: (id) arg1; // expected-note {{method 'compare:' declared
> here}}
>  @end
>
>  SEL func()
>  {
> -       return @selector(compare:);     // no warning on multiple selector
> found.
> +       return @selector(compare:);     // expected-warning {{several
> methods with selector 'compare:' of mismatched types are found for the
> @selector expression}}
>  }
>
>  int main() {
> @@ -27,3 +26,26 @@ int main() {
>
>   SEL s9 = @selector(:enum:bool:);
>  }
> +
> +// rdar://15794055
> + at interface NSObject @end
> +
> + at class NSNumber;
> +
> + at interface XBRecipe : NSObject
> + at property (nonatomic, assign) float finalVolume; // expected-note
> {{method 'setFinalVolume:' declared here}}
> + at end
> +
> + at interface XBDocument : NSObject
> + at end
> +
> + at interface XBDocument ()
> +- (void)setFinalVolume:(NSNumber *)finalVolumeNumber; // expected-note
> {{method 'setFinalVolume:' declared here}}
> + at end
> +
> + at implementation XBDocument
> +- (void)setFinalVolume:(NSNumber *)finalVolumeNumber
> +{
> +    (void)@selector(setFinalVolume:); // expected-warning {{several
> methods with selector 'setFinalVolume:' of mismatched types are found for
> the @selector expression}}
> +}
> + at end
>
>
> _______________________________________________
> cfe-commits mailing list
> cfe-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20140326/0d50aab4/attachment.html>


More information about the cfe-commits mailing list