Commit 29a4239d authored by Erik Pilkington's avatar Erik Pilkington
Browse files

[Sema] Fix a crash when attaching comments to an implicit decl 

When an implicitly generated decl was the first entry in the group, we
attempted to lookup comments with an empty FileID, leading to crashes. Avoid
this by trying to use the other declarations in the group, and then bailing out
if none are valid.

rdar://59919733
Differential revision: https://reviews.llvm.org/D75483
parent 44fa47c9

clang/lib/AST/ASTContext.cpp

+14 −4
Original line number Diff line number Diff line
@@ -474,10 +474,20 @@ void ASTContext::attachCommentsToJustParsedDecls(ArrayRef<Decl *> Decls, 
  if (Comments.empty() || Decls.empty())

    return;



  FileID File;

  for (Decl *D : Decls) {

    SourceLocation Loc = D->getLocation();

    if (Loc.isValid()) {

      // See if there are any new comments that are not attached to a decl.

      // The location doesn't have to be precise - we care only about the file.

  const FileID File =

      SourceMgr.getDecomposedLoc((*Decls.begin())->getLocation()).first;

      File = SourceMgr.getDecomposedLoc(Loc).first;

      break;

    }

  }



  if (File.isInvalid())

    return;



  auto CommentsInThisFile = Comments.getCommentsInFile(File);

  if (!CommentsInThisFile || CommentsInThisFile->empty() ||

      CommentsInThisFile->rbegin()->second->isAttached())

clang/test/Sema/warn-documentation.m

+8 −0
Original line number Diff line number Diff line 
// RUN: %clang_cc1 -fsyntax-only -fblocks -Wno-objc-root-class -Wdocumentation -Wdocumentation-pedantic -verify %s

// RUN: %clang_cc1 -xobjective-c++ -fsyntax-only -fblocks -Wno-objc-root-class -Wdocumentation -Wdocumentation-pedantic -verify %s



@class NSString;
@@ -318,3 +319,10 @@ VoidBlockTypeCall *d; ///< \return none 
// expected-warning@-1 {{'\return' command used in a comment that is not attached to a function or method declaration}}

VoidBlockTypeCall ^e; ///< \return none

// expected-warning@-1 {{'\return' command used in a comment that is not attached to a function or method declaration}}



#ifdef __cplusplus

@interface HasAnonNamespace @end

@implementation HasAnonNamespace

namespace {}

@end

#endif