[PATCH] D83961: [Analyzer] Fix bug report source locations in minimal output.

[Balázs Kéri via Phabricator via cfe-commits]

balazske added a comment.

>From the beginning on in this patch I assumed that the location of the bug report should be the end of the bug path. But this is probably a wrong approach, specially if the bug report has uniqueing location. In that case the uniqueing location may be a better place for the bug report. Specially for resource leak it is not bad if the report is located at the allocation site (still there is a bug path that shows the full path and place of leak). So another approach can be to allow only bug equivalence classes where the reports have same locations. If this is not true the checker should be fixed that generates the reports.

The behavior with `RefLeakReport` is correct if the indicated location in minimal output mode should be the end of the bug path. Otherwise it is not correct, the report has a different location (allocation site) than the end of the path (return point) and we want to see this in minimal mode (or not?). Still there is problem, in text output mode the summary line indicates not the correct place but the end of the bug path:
before the patch:

  $ clang -cc1 -internal-isystem ~/clang/llvm1/build/Debug/lib/clang/11.0.0/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -analyzer-checker=core,osx.cocoa.RetainCount -analyzer-store=region ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:9:23: warning: Potential leak of an object stored into 'X' [osx.cocoa.RetainCount]
    CGColorSpaceRef X = CGColorSpaceCreateDeviceRGB(); // expected-warning{{leak}}
                        ^
  1 warning generated.
  
  $ clang -cc1 -internal-isystem ~/clang/llvm1/build/Debug/lib/clang/11.0.0/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -analyzer-checker=core,osx.cocoa.RetainCount -analyzer-store=region ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c -analyzer-output text
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:11:1: warning: Potential leak of an object stored into 'X' [osx.cocoa.RetainCount]
  }
  ^
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:9:23: note: Call to function 'CGColorSpaceCreateDeviceRGB' returns a Core Foundation object of type 'CGColorSpaceRef' with a +1 retain count
    CGColorSpaceRef X = CGColorSpaceCreateDeviceRGB(); // expected-warning{{leak}}
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:10:3: note: Reference count incremented. The object now has a +2 retain count
    CGColorSpaceRetain(X);
    ^~~~~~~~~~~~~~~~~~~~~
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:11:1: note: Object leaked: object allocated and stored into 'X' is not referenced later in this execution path and has a retain count of +2
  }
  ^
  1 warning generated.

after the patch:

  $ clang -cc1 -internal-isystem ~/clang/llvm1/build/Debug/lib/clang/11.0.0/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -analyzer-checker=core,osx.cocoa.RetainCount -analyzer-store=region ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:11:1: warning: Potential leak of an object stored into 'X' [osx.cocoa.RetainCount]
  }
  ^
  1 warning generated.
  
  $ clang -cc1 -internal-isystem ~/clang/llvm1/build/Debug/lib/clang/11.0.0/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -analyzer-checker=core,osx.cocoa.RetainCount -analyzer-store=region ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c -analyzer-output text
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:11:1: warning: Potential leak of an object stored into 'X' [osx.cocoa.RetainCount]
  }
  ^
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:9:23: note: Call to function 'CGColorSpaceCreateDeviceRGB' returns a Core Foundation object of type 'CGColorSpaceRef' with a +1 retain count
    CGColorSpaceRef X = CGColorSpaceCreateDeviceRGB(); // expected-warning{{leak}}
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:10:3: note: Reference count incremented. The object now has a +2 retain count
    CGColorSpaceRetain(X);
    ^~~~~~~~~~~~~~~~~~~~~
  ~/clang/llvm1/llvm-project/clang/test/Analysis/CGColorSpace.c:11:1: note: Object leaked: object allocated and stored into 'X' is not referenced later in this execution path and has a retain count of +2
  }
  ^
  1 warning generated.

So it should be clarified how this should work, have the end of the bug path or the "location" of the bug report as display location of the bug report.


Repository:
  rG LLVM Github Monorepo

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https://reviews.llvm.org/D83961