diff options
| -rw-r--r-- | lib/Sema/SemaDecl.cpp | 9 | ||||
| -rw-r--r-- | test/SemaCXX/warn-unused-filescoped.cpp | 15 |
2 files changed, 22 insertions, 2 deletions
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp index e8d017c098..3576190310 100644 --- a/lib/Sema/SemaDecl.cpp +++ b/lib/Sema/SemaDecl.cpp @@ -1205,10 +1205,17 @@ bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { return false; } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { if (!VD->isFileVarDecl() || - VD->getType().isConstant(Context) || Context.DeclMustBeEmitted(VD)) return false; + // If a variable is usable in constant expressions and it's not odr-used, + // its value may still have been used. Conservatively suppress the warning + // in this case. + const VarDecl *VDWithInit = 0; + if (VD->isUsableInConstantExpressions(Context) && + VD->getAnyInitializer(VDWithInit) && VDWithInit->checkInitIsICE()) + return false; + if (VD->isStaticDataMember() && VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) return false; diff --git a/test/SemaCXX/warn-unused-filescoped.cpp b/test/SemaCXX/warn-unused-filescoped.cpp index dbff4b0e68..328d8bbb5b 100644 --- a/test/SemaCXX/warn-unused-filescoped.cpp +++ b/test/SemaCXX/warn-unused-filescoped.cpp @@ -1,4 +1,5 @@ -// RUN: %clang_cc1 -fsyntax-only -verify -Wunused -Wunused-member-function %s +// RUN: %clang_cc1 -fsyntax-only -verify -Wunused -Wunused-member-function -std=c++98 %s +// RUN: %clang_cc1 -fsyntax-only -verify -Wunused -Wunused-member-function -std=c++11 %s static void f1(); // expected-warning{{unused}} @@ -87,3 +88,15 @@ namespace rdar8733476 { foo(); } } + +namespace test5 { + static int n = 0; + static int &r = n; + int f(int &); + int k = f(r); + + static const int m = n; // expected-warning {{not needed and will not be emitted}} + int x = sizeof(m); + static const double d = 0.0; // expected-warning {{not needed and will not be emitted}} + int y = sizeof(d); +} |