[clang] [attributes][analyzer] Generalize [[clang::suppress]] to declarations. (PR #80371)

Artem Dergachev via cfe-commits cfe-commits at lists.llvm.org
Thu Feb 1 17:40:51 PST 2024


https://github.com/haoNoQ updated https://github.com/llvm/llvm-project/pull/80371

>From b702fcca1b4c5924ce4740d054e396aa4bc67e97 Mon Sep 17 00:00:00 2001
From: Artem Dergachev <adergachev at apple.com>
Date: Thu, 25 Jan 2024 18:05:39 -0800
Subject: [PATCH 1/2] [attributes][analyzer] Generalize [[clang::suppress]] to
 declarations.

The attribute is now allowed on an assortment of declarations, to suppress
warnings related to declarations themselves, or all warnings in
the lexical scope of the declaration.

I don't necessarily see a reason to have a list at all, but it does look
as if some of those more niche items aren't properly supported
by the compiler itself so let's maintain a short safe list for now.
---
 clang/include/clang/Basic/Attr.td             |  7 ++
 clang/include/clang/Basic/AttrDocs.td         | 23 +++++++
 clang/lib/Sema/SemaDecl.cpp                   |  3 +
 clang/lib/Sema/SemaDeclAttr.cpp               |  5 --
 .../Checkers/ObjCUnusedIVarsChecker.cpp       |  2 +-
 .../StaticAnalyzer/Core/BugSuppression.cpp    | 18 ++++-
 .../WebKit/ref-cntbl-base-virtual-dtor.cpp    | 10 +++
 .../WebKit/uncounted-lambda-captures.cpp      |  5 ++
 .../Checkers/WebKit/uncounted-local-vars.cpp  |  1 +
 .../Checkers/WebKit/uncounted-members.cpp     |  9 +++
 clang/test/Analysis/ObjCRetSigs.m             | 10 +++
 clang/test/Analysis/objc_invalidation.m       | 17 ++++-
 clang/test/Analysis/suppression-attr-doc.cpp  | 14 ++++
 clang/test/Analysis/suppression-attr.cpp      | 68 +++++++++++++++++++
 clang/test/Analysis/suppression-attr.m        | 60 ++++++++++++----
 clang/test/Analysis/unused-ivars.m            | 11 ++-
 clang/test/SemaCXX/attr-suppress.cpp          | 10 +--
 clang/test/SemaObjC/attr-suppress.m           | 19 ++----
 18 files changed, 250 insertions(+), 42 deletions(-)
 create mode 100644 clang/test/Analysis/suppression-attr.cpp

diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
index 58838b01b4fd7..1b37b01ba6a3f 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -2891,6 +2891,13 @@ def Suppress : DeclOrStmtAttr {
   let Spellings = [CXX11<"gsl", "suppress">, Clang<"suppress">];
   let Args = [VariadicStringArgument<"DiagnosticIdentifiers">];
   let Accessors = [Accessor<"isGSL", [CXX11<"gsl", "suppress">]>];
+  // There's no fundamental reason why we can't simply accept all Decls
+  // but let's make a short list so that to avoid supporting something weird
+  // by accident. We can always expand the list later.
+  let Subjects = SubjectList<[
+    Stmt, Var, Field, ObjCProperty, Function, ObjCMethod, Record, ObjCInterface,
+    ObjCImplementation, Namespace, Empty
+  ], ErrorDiag, "variables, functions, structs, interfaces, and namespaces">;
   let Documentation = [SuppressDocs];
 }
 
diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
index e02a1201e2ad7..a98d4b1f8d84d 100644
--- a/clang/include/clang/Basic/AttrDocs.td
+++ b/clang/include/clang/Basic/AttrDocs.td
@@ -5313,6 +5313,29 @@ Putting the attribute on a compound statement suppresses all warnings in scope:
     }
   }
 
+The attribute can also be placed on entire declarations of functions, classes,
+variables, member variables, and so on, to suppress warnings related
+to the declarations themselves. When used this way, the attribute additionally
+suppresses all warnings in the lexical scope of the declaration:
+
+.. code-block:: c++
+
+  class [[clang::suppress]] C {
+    int foo() {
+      int *x = nullptr;
+      ...
+      return *x;  // warnings suppressed in the entire class scope
+    }
+
+    int bar();
+  };
+
+  int C::bar() {
+    int *x = nullptr;
+    ...
+    return *x;  // warning NOT suppressed! - not lexically nested in 'class C{}'
+  }
+
 Some static analysis warnings are accompanied by one or more notes, and the
 line of code against which the warning is emitted isn't necessarily the best
 for suppression purposes. In such cases the tools are allowed to implement
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index fd1c47008d685..ca36d64cb077a 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -2960,6 +2960,9 @@ static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
         S.mergeHLSLNumThreadsAttr(D, *NT, NT->getX(), NT->getY(), NT->getZ());
   else if (const auto *SA = dyn_cast<HLSLShaderAttr>(Attr))
     NewAttr = S.mergeHLSLShaderAttr(D, *SA, SA->getType());
+  else if (const auto *SupA = dyn_cast<SuppressAttr>(Attr))
+    // Do nothing. Each redeclaration should be suppressed separately.
+    NewAttr = nullptr;
   else if (Attr->shouldInheritEvenIfAlreadyPresent() || !DeclHasAttr(D, Attr))
     NewAttr = cast<InheritableAttr>(Attr->clone(S.Context));
 
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index 069571fcf7864..3291ad732e98d 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -5245,11 +5245,6 @@ static void handleSuppressAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
     // Suppression attribute with GSL spelling requires at least 1 argument.
     if (!AL.checkAtLeastNumArgs(S, 1))
       return;
-  } else if (!isa<VarDecl>(D)) {
-    // Analyzer suppression applies only to variables and statements.
-    S.Diag(AL.getLoc(), diag::err_attribute_wrong_decl_type_str)
-        << AL << 0 << "variables and statements";
-    return;
   }
 
   std::vector<StringRef> DiagnosticIdentifiers;
diff --git a/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
index 1c2d84254d464..4f8750d9f1966 100644
--- a/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
@@ -161,7 +161,7 @@ static void checkObjCUnusedIvar(const ObjCImplementationDecl *D,
 
       PathDiagnosticLocation L =
           PathDiagnosticLocation::create(Ivar, BR.getSourceManager());
-      BR.EmitBasicReport(D, Checker, "Unused instance variable", "Optimization",
+      BR.EmitBasicReport(ID, Checker, "Unused instance variable", "Optimization",
                          os.str(), L);
     }
 }
diff --git a/clang/lib/StaticAnalyzer/Core/BugSuppression.cpp b/clang/lib/StaticAnalyzer/Core/BugSuppression.cpp
index fded071567f95..84004b8e5c1cd 100644
--- a/clang/lib/StaticAnalyzer/Core/BugSuppression.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugSuppression.cpp
@@ -82,12 +82,12 @@ class CacheInitializer : public RecursiveASTVisitor<CacheInitializer> {
     CacheInitializer(ToInit).TraverseDecl(const_cast<Decl *>(D));
   }
 
-  bool VisitVarDecl(VarDecl *VD) {
+  bool VisitDecl(Decl *D) {
     // Bug location could be somewhere in the init value of
     // a freshly declared variable.  Even though it looks like the
     // user applied attribute to a statement, it will apply to a
     // variable declaration, and this is where we check for it.
-    return VisitAttributedNode(VD);
+    return VisitAttributedNode(D);
   }
 
   bool VisitAttributedStmt(AttributedStmt *AS) {
@@ -147,6 +147,20 @@ bool BugSuppression::isSuppressed(const PathDiagnosticLocation &Location,
     // done as well as perform a lot of work we'll never need.
     // Gladly, none of our on-by-default checkers currently need it.
     DeclWithIssue = ACtx.getTranslationUnitDecl();
+  } else {
+    // This is the fast path. However, we should still consider the topmost
+    // declaration that isn't TranslationUnitDecl, because we should respect
+    // attributes on the entire declaration chain.
+    while (true) {
+      // Use the "lexical" parent. Eg., if the attribute is on a class, suppress
+      // warnings in inline methods but not in out-of-line methods.
+      const Decl *Parent =
+          dyn_cast_or_null<Decl>(DeclWithIssue->getLexicalDeclContext());
+      if (Parent == nullptr || isa<TranslationUnitDecl>(Parent))
+        break;
+
+      DeclWithIssue = Parent;
+    }
   }
 
   // While some warnings are attached to AST nodes (mostly path-sensitive
diff --git a/clang/test/Analysis/Checkers/WebKit/ref-cntbl-base-virtual-dtor.cpp b/clang/test/Analysis/Checkers/WebKit/ref-cntbl-base-virtual-dtor.cpp
index 1fc59c108b0e8..5cf7e7614d06e 100644
--- a/clang/test/Analysis/Checkers/WebKit/ref-cntbl-base-virtual-dtor.cpp
+++ b/clang/test/Analysis/Checkers/WebKit/ref-cntbl-base-virtual-dtor.cpp
@@ -13,7 +13,17 @@ struct DerivedWithVirtualDtor : RefCntblBase {
   virtual ~DerivedWithVirtualDtor() {}
 };
 
+// Confirm that the checker respects [[clang::suppress]]
+struct [[clang::suppress]] SuppressedDerived : RefCntblBase { };
+struct [[clang::suppress]] SuppressedDerivedWithVirtualDtor : RefCntblBase {
+  virtual ~SuppressedDerivedWithVirtualDtor() {}
+};
 
+// FIXME: Support attributes on base specifiers? Currently clang
+// doesn't support such attributes at all, even though it knows
+// how to parse them.
+//
+// struct SuppressedBaseSpecDerived : [[clang::suppress]] RefCntblBase { };
 
 template<class T>
 struct DerivedClassTmpl : T { };
diff --git a/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp b/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
index 30798793ceab1..27e0a74d583cd 100644
--- a/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
+++ b/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
@@ -15,6 +15,11 @@ void raw_ptr() {
   // CHECK-NEXT:{{^     | }}                     ^
   auto foo4 = [=](){ (void) ref_countable; };
   // CHECK: warning: Implicitly captured raw-pointer 'ref_countable' to uncounted type is unsafe [webkit.UncountedLambdaCapturesChecker]
+
+  // Confirm that the checker respects [[clang::suppress]].
+  RefCountable* suppressed_ref_countable = nullptr;
+  [[clang::suppress]] auto foo5 = [suppressed_ref_countable](){};
+  // CHECK-NOT: warning: Captured raw-pointer 'suppressed_ref_countable' to uncounted type is unsafe [webkit.UncountedLambdaCapturesChecker]
 }
 
 void references() {
diff --git a/clang/test/Analysis/Checkers/WebKit/uncounted-local-vars.cpp b/clang/test/Analysis/Checkers/WebKit/uncounted-local-vars.cpp
index 8694d5fb85b8b..0fcd3b21376ca 100644
--- a/clang/test/Analysis/Checkers/WebKit/uncounted-local-vars.cpp
+++ b/clang/test/Analysis/Checkers/WebKit/uncounted-local-vars.cpp
@@ -60,6 +60,7 @@ class Foo {
     // expected-warning at -1{{Local variable 'baz' is uncounted and unsafe [alpha.webkit.UncountedLocalVarsChecker]}}
     auto *baz2 = this->provide_ref_ctnbl();
     // expected-warning at -1{{Local variable 'baz2' is uncounted and unsafe [alpha.webkit.UncountedLocalVarsChecker]}}
+    [[clang::suppress]] auto *baz_suppressed = provide_ref_ctnbl(); // no-warning
   }
 };
 } // namespace auto_keyword
diff --git a/clang/test/Analysis/Checkers/WebKit/uncounted-members.cpp b/clang/test/Analysis/Checkers/WebKit/uncounted-members.cpp
index a0ea61e0e2a13..108d5effdd2e8 100644
--- a/clang/test/Analysis/Checkers/WebKit/uncounted-members.cpp
+++ b/clang/test/Analysis/Checkers/WebKit/uncounted-members.cpp
@@ -8,6 +8,9 @@ namespace members {
     RefCountable* a = nullptr;
 // expected-warning at -1{{Member variable 'a' in 'members::Foo' is a raw pointer to ref-countable type 'RefCountable'}}
 
+    [[clang::suppress]]
+    RefCountable* a_suppressed = nullptr;
+
   protected:
     RefPtr<RefCountable> b;
 
@@ -25,8 +28,14 @@ namespace members {
   };
 
   void forceTmplToInstantiate(FooTmpl<RefCountable>) {}
+
+  struct [[clang::suppress]] FooSuppressed {
+  private:
+    RefCountable* a = nullptr;
+  };
 }
 
+
 namespace ignore_unions {
   union Foo {
     RefCountable* a;
diff --git a/clang/test/Analysis/ObjCRetSigs.m b/clang/test/Analysis/ObjCRetSigs.m
index 97d33f9f5467b..f92506a834195 100644
--- a/clang/test/Analysis/ObjCRetSigs.m
+++ b/clang/test/Analysis/ObjCRetSigs.m
@@ -4,10 +4,12 @@
 
 @interface MyBase
 -(long long)length;
+-(long long)suppressedLength;
 @end
 
 @interface MySub : MyBase{}
 -(double)length;
+-(double)suppressedLength;
 @end
 
 @implementation MyBase
@@ -15,6 +17,10 @@ -(long long)length{
    printf("Called MyBase -length;\n");
    return 3;
 }
+-(long long)suppressedLength{
+   printf("Called MyBase -length;\n");
+   return 3;
+}
 @end
 
 @implementation MySub
@@ -22,4 +28,8 @@ -(double)length{  // expected-warning{{types are incompatible}}
    printf("Called MySub -length;\n");
    return 3.3;
 }
+-(double)suppressedLength [[clang::suppress]]{ // no-warning
+   printf("Called MySub -length;\n");
+   return 3.3;
+}
 @end
diff --git a/clang/test/Analysis/objc_invalidation.m b/clang/test/Analysis/objc_invalidation.m
index 52a79d8f34baa..e61b0897646a2 100644
--- a/clang/test/Analysis/objc_invalidation.m
+++ b/clang/test/Analysis/objc_invalidation.m
@@ -257,6 +257,17 @@ @interface MissingInvalidationMethod : Foo <FooBar_Protocol>
 @implementation MissingInvalidationMethod
 @end
 
+ at interface SuppressedMissingInvalidationMethod : Foo <FooBar_Protocol>
+ at property (assign) [[clang::suppress]] SuppressedMissingInvalidationMethod *foobar16_warn;
+// FIXME: Suppression should have worked but decl-with-issue is the ivar, not the property.
+#if RUN_IVAR_INVALIDATION
+// expected-warning at -3 {{Property foobar16_warn needs to be invalidated; no invalidation method is defined in the @implementation for SuppressedMissingInvalidationMethod}}
+#endif
+
+ at end
+ at implementation SuppressedMissingInvalidationMethod
+ at end
+
 @interface MissingInvalidationMethod2 : Foo <FooBar_Protocol> {
   Foo *Ivar1;
 #if RUN_IVAR_INVALIDATION
@@ -290,8 +301,10 @@ @implementation MissingInvalidationMethodDecl2
 @end
 
 @interface InvalidatedInPartial : SomeInvalidationImplementingObject {
-  SomeInvalidationImplementingObject *Ivar1; 
-  SomeInvalidationImplementingObject *Ivar2; 
+  SomeInvalidationImplementingObject *Ivar1;
+  SomeInvalidationImplementingObject *Ivar2;
+  [[clang::suppress]]
+  SomeInvalidationImplementingObject *Ivar3; // no-warning
 }
 -(void)partialInvalidator __attribute__((annotate("objc_instance_variable_invalidator_partial")));
 @end
diff --git a/clang/test/Analysis/suppression-attr-doc.cpp b/clang/test/Analysis/suppression-attr-doc.cpp
index 1208842799ed9..ca4e665a082ce 100644
--- a/clang/test/Analysis/suppression-attr-doc.cpp
+++ b/clang/test/Analysis/suppression-attr-doc.cpp
@@ -52,3 +52,17 @@ int bar2(bool coin_flip) {
   __attribute__((suppress))
   return *result;  // leak warning is suppressed only on this path
 }
+
+class [[clang::suppress]] C {
+  int foo() {
+    int *x = nullptr;
+    return *x;  // warnings suppressed in the entire class
+  }
+
+  int bar();
+};
+
+int C::bar() {
+  int *x = nullptr;
+  return *x;  // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
+}
diff --git a/clang/test/Analysis/suppression-attr.cpp b/clang/test/Analysis/suppression-attr.cpp
new file mode 100644
index 0000000000000..89bc3c47dbd51
--- /dev/null
+++ b/clang/test/Analysis/suppression-attr.cpp
@@ -0,0 +1,68 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=core -verify %s
+
+namespace [[clang::suppress]]
+suppressed_namespace {
+  int foo() {
+    int *x = 0;
+    return *x;
+  }
+
+  int foo_forward();
+}
+
+int suppressed_namespace::foo_forward() {
+    int *x = 0;
+    return *x; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
+}
+
+// Another instance of the same namespace.
+namespace suppressed_namespace {
+  int bar() {
+    int *x = 0;
+    return *x; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
+  }
+}
+
+void lambda() {
+  [[clang::suppress]] {
+    auto lam = []() {
+      int *x = 0;
+      return *x;
+    };
+  }
+}
+
+class [[clang::suppress]] SuppressedClass {
+  int foo() {
+    int *x = 0;
+    return *x;
+  }
+
+  int bar();
+};
+
+int SuppressedClass::bar() {
+  int *x = 0;
+  return *x; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
+}
+
+class SuppressedMethodClass {
+  [[clang::suppress]] int foo() {
+    int *x = 0;
+    return *x;
+  }
+
+  [[clang::suppress]] int bar1();
+  int bar2();
+};
+
+int SuppressedMethodClass::bar1() {
+  int *x = 0;
+  return *x; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
+}
+
+[[clang::suppress]]
+int SuppressedMethodClass::bar2() {
+  int *x = 0;
+  return *x; // no-warning
+}
diff --git a/clang/test/Analysis/suppression-attr.m b/clang/test/Analysis/suppression-attr.m
index 8ba8dda722721..acef4b34fb09f 100644
--- a/clang/test/Analysis/suppression-attr.m
+++ b/clang/test/Analysis/suppression-attr.m
@@ -168,17 +168,15 @@ void malloc_leak_suppression_2_1() {
   *x = 42;
 }
 
-// TODO: reassess when we decide what to do with declaration annotations
-void malloc_leak_suppression_2_2() /* SUPPRESS */ {
+void malloc_leak_suppression_2_2() SUPPRESS {
   int *x = (int *)malloc(sizeof(int));
   *x = 42;
-} // expected-warning{{Potential leak of memory pointed to by 'x'}}
+} // no-warning
 
-// TODO: reassess when we decide what to do with declaration annotations
-/* SUPPRESS */ void malloc_leak_suppression_2_3() {
+SUPPRESS void malloc_leak_suppression_2_3() {
   int *x = (int *)malloc(sizeof(int));
   *x = 42;
-} // expected-warning{{Potential leak of memory pointed to by 'x'}}
+} // no-warning
 
 void malloc_leak_suppression_2_4(int cond) {
   int *x = (int *)malloc(sizeof(int));
@@ -233,20 +231,15 @@ - (void)methodWhichMayFail:(NSError **)error {
 
 @interface TestSuppress : UIResponder {
 }
-// TODO: reassess when we decide what to do with declaration annotations
- at property(copy) /* SUPPRESS */ NSMutableString *mutableStr;
-// expected-warning at -1 {{Property of mutable type 'NSMutableString' has 'copy' attribute; an immutable object will be stored instead}}
+ at property(copy) SUPPRESS NSMutableString *mutableStr; // no-warning
 @end
 @implementation TestSuppress
 
-// TODO: reassess when we decide what to do with declaration annotations
-- (BOOL)resignFirstResponder /* SUPPRESS */ {
+- (BOOL)resignFirstResponder SUPPRESS { // no-warning
   return 0;
-} // expected-warning {{The 'resignFirstResponder' instance method in UIResponder subclass 'TestSuppress' is missing a [super resignFirstResponder] call}}
+}
 
-// TODO: reassess when we decide what to do with declaration annotations
-- (void)methodWhichMayFail:(NSError **)error /* SUPPRESS */ {
-  // expected-warning at -1 {{Method accepting NSError** should have a non-void return value to indicate whether or not an error occurred}}
+- (void)methodWhichMayFail:(NSError **)error SUPPRESS { // no-warning
 }
 @end
 
@@ -269,3 +262,40 @@ void ast_checker_suppress_1() {
   struct ABC *Abc;
   SUPPRESS { Abc = (struct ABC *)&Ab; }
 }
+
+SUPPRESS int suppressed_function() {
+  int *x = 0;
+  return *x; // no-warning
+}
+
+SUPPRESS int suppressed_function_forward();
+int suppressed_function_forward() {
+  int *x = 0;
+  return *x; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
+}
+
+int suppressed_function_backward();
+SUPPRESS int suppressed_function_backward() {
+  int *x = 0;
+  return *x; // no-warning
+}
+
+SUPPRESS
+ at interface SuppressedInterface
+-(int)suppressedMethod;
+-(int)regularMethod SUPPRESS;
+ at end
+
+ at implementation SuppressedInterface
+-(int)suppressedMethod SUPPRESS {
+  int *x = 0;
+  return *x; // no-warning
+}
+
+// This one is NOT suppressed by the attribute on the forward declaration,
+// and it's also NOT suppressed by the attribute on the entire interface.
+-(int)regularMethod {
+  int *x = 0;
+  return *x; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
+}
+ at end
diff --git a/clang/test/Analysis/unused-ivars.m b/clang/test/Analysis/unused-ivars.m
index 32e7e80fc4276..8788804bf0c33 100644
--- a/clang/test/Analysis/unused-ivars.m
+++ b/clang/test/Analysis/unused-ivars.m
@@ -44,6 +44,15 @@ - (void)setIvar:(id)newValue {
 }
 @end
 
+// Confirm that the checker respects [[clang::suppress]].
+ at interface TestC {
+ at private
+  [[clang::suppress]] int x; // no-warning
+}
+ at end
+ at implementation TestC @end
+
+
 //===----------------------------------------------------------------------===//
 // Detect that ivar is in use, if used in category in the same file as the
 // implementation.
@@ -125,4 +134,4 @@ @implementation Radar11059352
 - (void)useWorkspace {
     NSString *workspacePathString = _workspacePath.pathString;
 }
- at end
\ No newline at end of file
+ at end
diff --git a/clang/test/SemaCXX/attr-suppress.cpp b/clang/test/SemaCXX/attr-suppress.cpp
index fb5e2ac7ce206..e8f6d97988091 100644
--- a/clang/test/SemaCXX/attr-suppress.cpp
+++ b/clang/test/SemaCXX/attr-suppress.cpp
@@ -23,18 +23,16 @@ union [[gsl::suppress("type.1")]] U {
   float f;
 };
 
+// This doesn't really suppress anything but why not?
 [[clang::suppress]];
-// expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
 
 namespace N {
 [[clang::suppress("in-a-namespace")]];
-// expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
 } // namespace N
 
 [[clang::suppress]] int global = 42;
 
 [[clang::suppress]] void foo() {
-  // expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
   [[clang::suppress]] int *p;
 
   [[clang::suppress]] int a = 0;           // no-warning
@@ -56,7 +54,11 @@ namespace N {
 }
 
 class [[clang::suppress("type.1")]] V {
-  // expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
   int i;
   float f;
 };
+
+// FIXME: There's no good reason why we shouldn't support this case.
+// But it doesn't look like clang generally supports such attributes yet.
+class W : [[clang::suppress]] public V { // expected-error{{'suppress' attribute cannot be applied to a base specifier}}
+};
diff --git a/clang/test/SemaObjC/attr-suppress.m b/clang/test/SemaObjC/attr-suppress.m
index ade8f94ec5895..c12da097bf844 100644
--- a/clang/test/SemaObjC/attr-suppress.m
+++ b/clang/test/SemaObjC/attr-suppress.m
@@ -6,8 +6,7 @@
 SUPPRESS1 int global = 42;
 
 SUPPRESS1 void foo() {
-  // expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
-  SUPPRESS1 int *p;
+  SUPPRESS1 int *p; // no-warning
 
   SUPPRESS1 int a = 0; // no-warning
   SUPPRESS2()
@@ -28,23 +27,19 @@ SUPPRESS1 switch (a) { // no-warning
   // GNU-style attributes and C++11 attributes apply to different things when
   // written like this.  GNU  attribute gets attached to the declaration, while
   // C++11 attribute ends up on the type.
-  int SUPPRESS2("r") z;
-  SUPPRESS2(foo)
+  int SUPPRESS2("r") z; // no-warning
+  SUPPRESS2(foo) // no-warning
   float f;
   // expected-error at -2 {{expected string literal as argument of 'suppress' attribute}}
 }
 
-union SUPPRESS2("type.1") U {
-  // expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
+union SUPPRESS2("type.1") U { // no-warning
   int i;
   float f;
 };
 
-SUPPRESS1 @interface Test {
-  // expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
+SUPPRESS1 @interface Test { // no-warning
 }
- at property SUPPRESS2("prop") int *prop;
-// expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
-- (void)bar:(int)x SUPPRESS1;
-// expected-error at -1 {{'suppress' attribute only applies to variables and statements}}
+ at property SUPPRESS2("prop") int *prop; // no-warning
+- (void)bar:(int)x SUPPRESS1; // no-warning
 @end

>From c1f9b5c811ffed45e3ac813426f2e6283dea7acc Mon Sep 17 00:00:00 2001
From: Artem Dergachev <adergachev at apple.com>
Date: Thu, 1 Feb 2024 17:40:37 -0800
Subject: [PATCH 2/2] Fix formatting.

---
 clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
index 4f8750d9f1966..2f2df63468b4b 100644
--- a/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
@@ -161,8 +161,8 @@ static void checkObjCUnusedIvar(const ObjCImplementationDecl *D,
 
       PathDiagnosticLocation L =
           PathDiagnosticLocation::create(Ivar, BR.getSourceManager());
-      BR.EmitBasicReport(ID, Checker, "Unused instance variable", "Optimization",
-                         os.str(), L);
+      BR.EmitBasicReport(ID, Checker, "Unused instance variable",
+                         "Optimization", os.str(), L);
     }
 }
 



More information about the cfe-commits mailing list