Commit improved version of 111026 & 111027.
Unused warnings for functions:
-static functions
-functions in anonymous namespace
-class methods in anonymous namespace
-class method specializations in anonymous namespace
-function specializations in anonymous namespace
Unused warnings for variables:
-static variables
-variables in anonymous namespace
-static data members in anonymous namespace
-static data members specializations in anonymous namespace
Reveals lots of opportunities for dead code removal in llvm codebase that will
interest my esteemed colleagues.
llvm-svn: 111086
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index e1f9c82..ea65c8c 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -521,25 +521,71 @@
F.done();
}
-static bool ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) {
- if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
- // Warn for static, non-inlined function definitions that
- // have not been used.
- // FIXME: Also include static functions declared but not defined.
- return (!FD->isInvalidDecl()
- && !FD->isInlined() && FD->getLinkage() == InternalLinkage
- && !FD->isUsed() && !FD->hasAttr<UnusedAttr>()
- && !FD->hasAttr<ConstructorAttr>()
- && !FD->hasAttr<DestructorAttr>());
- }
-
- return false;
-}
+bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
+ assert(D);
-void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
- if (ShouldWarnIfUnusedFileScopedDecl(D))
- UnusedFileScopedDecls.push_back(D);
-}
+ if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
+ return false;
+
+ // Ignore class templates.
+ if (D->getDeclContext()->isDependentContext())
+ return false;
+
+ // We warn for unused decls internal to the translation unit.
+ if (D->getLinkage() == ExternalLinkage)
+ return false;
+
+ if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+ if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
+ return false;
+
+ if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
+ if (MD->isVirtual())
+ return false;
+ } else {
+ // 'static inline' functions are used in headers; don't warn.
+ if (FD->getStorageClass() == FunctionDecl::Static &&
+ FD->isInlineSpecified())
+ return false;
+ }
+
+ if (FD->isThisDeclarationADefinition())
+ return !Context.DeclMustBeEmitted(FD);
+ return true;
+ }
+
+ if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
+ if (VD->isStaticDataMember() &&
+ VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
+ return false;
+
+ if ( VD->isFileVarDecl() &&
+ !VD->getType().isConstant(Context))
+ return !Context.DeclMustBeEmitted(VD);
+ }
+
+ return false;
+ }
+
+ void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
+ if (!D)
+ return;
+
+ if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+ const FunctionDecl *First = FD->getFirstDeclaration();
+ if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
+ return; // First should already be in the vector.
+ }
+
+ if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
+ const VarDecl *First = VD->getFirstDeclaration();
+ if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
+ return; // First should already be in the vector.
+ }
+
+ if (ShouldWarnIfUnusedFileScopedDecl(D))
+ UnusedFileScopedDecls.push_back(D);
+ }
static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
if (D->isInvalidDecl())
@@ -2743,6 +2789,8 @@
if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord())
AddPushedVisibilityAttribute(NewVD);
+ MarkUnusedFileScopedDecl(NewVD);
+
return NewVD;
}
@@ -3638,8 +3686,7 @@
if (FunctionTemplate)
return FunctionTemplate;
- if (IsFunctionDefinition)
- MarkUnusedFileScopedDecl(NewFD);
+ MarkUnusedFileScopedDecl(NewFD);
return NewFD;
}