Commit 5260bc24 authored by Etienne Pierre-Doray's avatar Etienne Pierre-Doray Committed by Aaron Ballman
Browse files

Allow arbitrary capability name in Thread Safety Analysis 

Restricting the names of capabilities to only "role" or "mutex" makes
for awkward diagnostic text, such as with:
https://chromium-review.googlesource.com/c/chromium/src/+/1948098/19/base/sequence_checker_unittest.nc#33
parent b6c62ef0

clang/include/clang/Basic/Attr.td

+0 −4
Original line number Diff line number Diff line
@@ -2567,10 +2567,6 @@ def Capability : InheritableAttr { 
  let Accessors = [Accessor<"isShared",

                    [Clang<"shared_capability", 0>]>];

  let Documentation = [Undocumented];

  let AdditionalMembers = [{

    bool isMutex() const { return getName().equals_lower("mutex"); }

    bool isRole() const { return getName().equals_lower("role"); }

  }];

}



def AssertCapability : InheritableAttr {

clang/include/clang/Basic/DiagnosticSemaKinds.td

+0 −3
Original line number Diff line number Diff line
@@ -3252,9 +3252,6 @@ def warn_at_available_unchecked_use : Warning< 
  InGroup<DiagGroup<"unsupported-availability-guard">>;















// Thread Safety Attributes













def warn_invalid_capability_name : Warning<













  "invalid capability name '%0'; capability name must be 'mutex' or 'role'">,













  InGroup<ThreadSafetyAttributes>, DefaultIgnore;















def warn_thread_attribute_ignored : Warning<















  "ignoring %0 attribute because its argument is invalid">,















  InGroup<ThreadSafetyAttributes>, DefaultIgnore;

































clang/lib/Sema/SemaDeclAttr.cpp



+0
−5






























Original line number
Diff line number
Diff line








@@ -6195,11 +6195,6 @@ static void handleCapabilityAttr(Sema &S, Decl *D, const ParsedAttr &AL) {













      !S.checkStringLiteralArgumentAttr(AL, 0, N, &LiteralLoc))















    return;





























  // Currently, there are only two names allowed for a capability: role and













  // mutex (case insensitive). Diagnose other capability names.













  if (!N.equals_lower("mutex") && !N.equals_lower("role"))













    S.Diag(LiteralLoc, diag::warn_invalid_capability_name) << N;





























  D->addAttr(::new (S.Context) CapabilityAttr(S.Context, AL, N));















}

















































clang/test/Sema/attr-capabilities.c



+3
−2






























Original line number
Diff line number
Diff line















// RUN: %clang_cc1 -fsyntax-only -Wthread-safety -verify %s





























typedef int __attribute__((capability("role"))) ThreadRole;















typedef int __attribute__((capability("role"))) ThreadRole;















struct __attribute__((shared_capability("mutex"))) Mutex {};















struct NotACapability {};









@@ -8,8 +9,8 @@ struct NotACapability {};













union __attribute__((capability("mutex"))) MutexUnion { int a; char* b; };















typedef union { int a; char* b; } __attribute__((capability("mutex"))) MutexUnion2;





























// Test an invalid capability name













struct __attribute__((capability("wrong"))) IncorrectName {}; // expected-warning {{invalid capability name 'wrong'; capability name must be 'mutex' or 'role'}}













// Test a different capability name













struct __attribute__((capability("custom"))) CustomName {};































int Test1 __attribute__((capability("test1")));  // expected-error {{'capability' attribute only applies to structs, unions, classes, and typedefs}}















int Test2 __attribute__((shared_capability("test2"))); // expected-error {{'shared_capability' attribute only applies to structs, unions, classes, and typedefs}}