On Thu, Sep 4, 2014 at 10:36 AM, Hans Wennborg <[email protected]> wrote: > On Thu, Sep 4, 2014 at 10:33 AM, Reid Kleckner <[email protected]> wrote: >> Can we merge this to 3.5, or are we done merging patches? > > 3.5-final was tagged a few days ago. I'd be fine with merging this for > 3.5.1, though.
Tom, may I merge this to the branch? This was discussed on the bug too: http://llvm.org/bugs/show_bug.cgi?id=20746#c12 Thanks, Hans >> On Wed, Aug 27, 2014 at 2:27 PM, Hans Wennborg <[email protected]> wrote: >>> >>> Author: hans >>> Date: Wed Aug 27 16:27:40 2014 >>> New Revision: 216619 >>> >>> URL: http://llvm.org/viewvc/llvm-project?rev=216619&view=rev >>> Log: >>> Allow adding dll attributes on certain redecls with a warning if the decl >>> hasn't been used yet (PR20746) >>> >>> This shouldn't really be allowed, but it comes up in real code (see PR). >>> As >>> long as the decl hasn't been used there's no technical difficulty in >>> supporting >>> it, so downgrade the error to a warning. >>> >>> Differential Revision: http://reviews.llvm.org/D5087 >>> >>> Modified: >>> cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td >>> cfe/trunk/lib/Sema/SemaDecl.cpp >>> cfe/trunk/test/Sema/dllexport.c >>> cfe/trunk/test/Sema/dllimport.c >>> cfe/trunk/test/SemaCXX/dllexport.cpp >>> cfe/trunk/test/SemaCXX/dllimport.cpp >>> >>> Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=216619&r1=216618&r2=216619&view=diff >>> >>> ============================================================================== >>> --- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original) >>> +++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Wed Aug 27 >>> 16:27:40 2014 >>> @@ -2133,6 +2133,9 @@ def warn_attribute_invalid_on_definition >>> InGroup<IgnoredAttributes>; >>> def err_attribute_dll_redeclaration : Error< >>> "redeclaration of %q0 cannot add %q1 attribute">; >>> +def warn_attribute_dll_redeclaration : Warning< >>> + "redeclaration of %q0 should not add %q1 attribute">, >>> + InGroup<DiagGroup<"dll-attribute-on-redeclaration">>; >>> def err_attribute_dllimport_function_definition : Error< >>> "dllimport cannot be applied to non-inline function definition">; >>> def err_attribute_dll_deleted : Error< >>> >>> Modified: cfe/trunk/lib/Sema/SemaDecl.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=216619&r1=216618&r2=216619&view=diff >>> >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaDecl.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaDecl.cpp Wed Aug 27 16:27:40 2014 >>> @@ -5075,7 +5075,7 @@ static void checkDLLAttributeRedeclarati >>> NewDecl = NewTD->getTemplatedDecl(); >>> >>> if (!OldDecl || !NewDecl) >>> - return; >>> + return; >>> >>> const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>(); >>> const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>(); >>> @@ -5092,13 +5092,30 @@ static void checkDLLAttributeRedeclarati >>> // Implicitly generated declarations are also excluded for now because >>> there >>> // is no other way to switch these to use dllimport or dllexport. >>> bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr; >>> + >>> if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) { >>> - S.Diag(NewDecl->getLocation(), diag::err_attribute_dll_redeclaration) >>> - << NewDecl >>> - << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr); >>> + // If the declaration hasn't been used yet, allow with a warning for >>> + // free functions and global variables. >>> + bool JustWarn = false; >>> + if (!OldDecl->isUsed() && OldDecl->getDeclContext()->isFileContext()) >>> { >>> + auto *VD = dyn_cast<VarDecl>(OldDecl); >>> + if (VD && !VD->getDescribedVarTemplate()) >>> + JustWarn = true; >>> + auto *FD = dyn_cast<FunctionDecl>(OldDecl); >>> + if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate) >>> + JustWarn = true; >>> + } >>> + >>> + unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration >>> + : diag::err_attribute_dll_redeclaration; >>> + S.Diag(NewDecl->getLocation(), DiagID) >>> + << NewDecl >>> + << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr); >>> S.Diag(OldDecl->getLocation(), diag::note_previous_declaration); >>> - NewDecl->setInvalidDecl(); >>> - return; >>> + if (!JustWarn) { >>> + NewDecl->setInvalidDecl(); >>> + return; >>> + } >>> } >>> >>> // A redeclaration is not allowed to drop a dllimport attribute, the >>> only >>> >>> Modified: cfe/trunk/test/Sema/dllexport.c >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/dllexport.c?rev=216619&r1=216618&r2=216619&view=diff >>> >>> ============================================================================== >>> --- cfe/trunk/test/Sema/dllexport.c (original) >>> +++ cfe/trunk/test/Sema/dllexport.c Wed Aug 27 16:27:40 2014 >>> @@ -39,8 +39,13 @@ __declspec(dllexport) extern int GlobalR >>> int GlobalRedecl2; >>> >>> extern int GlobalRedecl3; // >>> expected-note{{previous declaration is here}} >>> +int useGlobalRedecl3() { return GlobalRedecl3; } >>> __declspec(dllexport) extern int GlobalRedecl3; // >>> expected-error{{redeclaration of 'GlobalRedecl3' cannot add 'dllexport' >>> attribute}} >>> >>> + extern int GlobalRedecl4; // >>> expected-note{{previous declaration is here}} >>> +__declspec(dllexport) extern int GlobalRedecl4; // >>> expected-warning{{redeclaration of 'GlobalRedecl4' should not add >>> 'dllexport' attribute}} >>> + >>> + >>> // External linkage is required. >>> __declspec(dllexport) static int StaticGlobal; // >>> expected-error{{'StaticGlobal' must have external linkage when declared >>> 'dllexport'}} >>> >>> @@ -86,11 +91,18 @@ __declspec(dllexport) void redecl3(); >>> void redecl3() {} >>> >>> void redecl4(); // expected-note{{previous >>> declaration is here}} >>> +void useRedecl4() { redecl4(); } >>> __declspec(dllexport) void redecl4(); // expected-error{{redeclaration of >>> 'redecl4' cannot add 'dllexport' attribute}} >>> >>> void redecl5(); // expected-note{{previous >>> declaration is here}} >>> +void useRedecl5() { redecl5(); } >>> __declspec(dllexport) inline void redecl5() {} // >>> expected-error{{redeclaration of 'redecl5' cannot add 'dllexport' >>> attribute}} >>> >>> +// Allow with a warning if the decl hasn't been used yet. >>> + void redecl6(); // expected-note{{previous >>> declaration is here}} >>> +__declspec(dllexport) void redecl6(); // expected-warning{{redeclaration >>> of 'redecl6' should not add 'dllexport' attribute}} >>> + >>> + >>> // External linkage is required. >>> __declspec(dllexport) static int staticFunc(); // >>> expected-error{{'staticFunc' must have external linkage when declared >>> 'dllexport'}} >>> >>> >>> Modified: cfe/trunk/test/Sema/dllimport.c >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/dllimport.c?rev=216619&r1=216618&r2=216619&view=diff >>> >>> ============================================================================== >>> --- cfe/trunk/test/Sema/dllimport.c (original) >>> +++ cfe/trunk/test/Sema/dllimport.c Wed Aug 27 16:27:40 2014 >>> @@ -64,9 +64,16 @@ int GlobalRedecl2c __attribute__((dllimp >>> __declspec(dllimport) extern int GlobalRedecl3; // >>> expected-note{{previous declaration is here}} expected-note{{previous >>> attribute is here}} >>> extern int GlobalRedecl3; // >>> expected-warning{{'GlobalRedecl3' redeclared without 'dllimport' attribute: >>> previous 'dllimport' ignored}} >>> >>> +// Adding an attribute on redeclaration. >>> extern int GlobalRedecl4; // >>> expected-note{{previous declaration is here}} >>> +int useGlobalRedecl4() { return GlobalRedecl4; } >>> __declspec(dllimport) extern int GlobalRedecl4; // >>> expected-error{{redeclaration of 'GlobalRedecl4' cannot add 'dllimport' >>> attribute}} >>> >>> +// Allow with a warning if the decl hasn't been used yet. >>> + extern int GlobalRedecl5; // >>> expected-note{{previous declaration is here}} >>> +__declspec(dllimport) extern int GlobalRedecl5; // >>> expected-warning{{redeclaration of 'GlobalRedecl5' should not add >>> 'dllimport' attribute}} >>> + >>> + >>> // External linkage is required. >>> __declspec(dllimport) static int StaticGlobal; // >>> expected-error{{'StaticGlobal' must have external linkage when declared >>> 'dllimport'}} >>> >>> @@ -128,14 +135,20 @@ __declspec(dllimport) void redecl3(); // >>> void redecl3() {} // expected-warning{{'redecl3' >>> redeclared without 'dllimport' attribute: previous 'dllimport' ignored}} >>> >>> void redecl4(); // expected-note{{previous >>> declaration is here}} >>> +void useRedecl4() { redecl4(); } >>> __declspec(dllimport) void redecl4(); // expected-error{{redeclaration of >>> 'redecl4' cannot add 'dllimport' attribute}} >>> >>> +// Allow with a warning if the decl hasn't been used yet. >>> + void redecl5(); // expected-note{{previous >>> declaration is here}} >>> +__declspec(dllimport) void redecl5(); // expected-warning{{redeclaration >>> of 'redecl5' should not add 'dllimport' attribute}} >>> + >>> + >>> // Inline redeclarations are fine. >>> -__declspec(dllimport) void redecl5(); >>> - inline void redecl5() {} >>> +__declspec(dllimport) void redecl6(); >>> + inline void redecl6() {} >>> >>> - void redecl6(); // expected-note{{previous >>> declaration is here}} >>> -__declspec(dllimport) inline void redecl6() {} // >>> expected-error{{redeclaration of 'redecl6' cannot add 'dllimport' >>> attribute}} >>> + void redecl7(); // expected-note{{previous >>> declaration is here}} >>> +__declspec(dllimport) inline void redecl7() {} // >>> expected-warning{{redeclaration of 'redecl7' should not add 'dllimport' >>> attribute}} >>> >>> // External linkage is required. >>> __declspec(dllimport) static int staticFunc(); // >>> expected-error{{'staticFunc' must have external linkage when declared >>> 'dllimport'}} >>> >>> Modified: cfe/trunk/test/SemaCXX/dllexport.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/dllexport.cpp?rev=216619&r1=216618&r2=216619&view=diff >>> >>> ============================================================================== >>> --- cfe/trunk/test/SemaCXX/dllexport.cpp (original) >>> +++ cfe/trunk/test/SemaCXX/dllexport.cpp Wed Aug 27 16:27:40 2014 >>> @@ -53,7 +53,7 @@ __declspec(dllexport) extern int GlobalR >>> int GlobalRedecl2; >>> >>> extern int GlobalRedecl3; // >>> expected-note{{previous declaration is here}} >>> -__declspec(dllexport) extern int GlobalRedecl3; // >>> expected-error{{redeclaration of 'GlobalRedecl3' cannot add 'dllexport' >>> attribute}} >>> +__declspec(dllexport) extern int GlobalRedecl3; // >>> expected-warning{{redeclaration of 'GlobalRedecl3' should not add >>> 'dllexport' attribute}} >>> >>> // External linkage is required. >>> __declspec(dllexport) static int StaticGlobal; // >>> expected-error{{'StaticGlobal' must have external linkage when declared >>> 'dllexport'}} >>> @@ -186,10 +186,10 @@ __declspec(dllexport) void redecl2(); >>> void redecl2() {} >>> >>> void redecl3(); // expected-note{{previous >>> declaration is here}} >>> -__declspec(dllexport) void redecl3(); // expected-error{{redeclaration of >>> 'redecl3' cannot add 'dllexport' attribute}} >>> +__declspec(dllexport) void redecl3(); // expected-warning{{redeclaration >>> of 'redecl3' should not add 'dllexport' attribute}} >>> >>> void redecl4(); // expected-note{{previous >>> declaration is here}} >>> -__declspec(dllexport) inline void redecl4() {} // >>> expected-error{{redeclaration of 'redecl4' cannot add 'dllexport' >>> attribute}} >>> +__declspec(dllexport) inline void redecl4() {} // >>> expected-warning{{redeclaration of 'redecl4' should not add 'dllexport' >>> attribute}} >>> >>> // Friend functions >>> struct FuncFriend { >>> @@ -200,8 +200,8 @@ struct FuncFriend { >>> }; >>> __declspec(dllexport) void friend1() {} >>> void friend2() {} >>> -__declspec(dllexport) void friend3() {} // expected-error{{redeclaration >>> of 'friend3' cannot add 'dllexport' attribute}} >>> -__declspec(dllexport) inline void friend4() {} // >>> expected-error{{redeclaration of 'friend4' cannot add 'dllexport' >>> attribute}} >>> +__declspec(dllexport) void friend3() {} // >>> expected-warning{{redeclaration of 'friend3' should not add 'dllexport' >>> attribute}} >>> +__declspec(dllexport) inline void friend4() {} // >>> expected-warning{{redeclaration of 'friend4' should not add 'dllexport' >>> attribute}} >>> >>> // Implicit declarations can be redeclared with dllexport. >>> __declspec(dllexport) void* operator new(__SIZE_TYPE__ n); >>> >>> Modified: cfe/trunk/test/SemaCXX/dllimport.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/dllimport.cpp?rev=216619&r1=216618&r2=216619&view=diff >>> >>> ============================================================================== >>> --- cfe/trunk/test/SemaCXX/dllimport.cpp (original) >>> +++ cfe/trunk/test/SemaCXX/dllimport.cpp Wed Aug 27 16:27:40 2014 >>> @@ -75,7 +75,7 @@ __declspec(dllimport) extern int GlobalR >>> extern int GlobalRedecl3; // >>> expected-warning{{'GlobalRedecl3' redeclared without 'dllimport' attribute: >>> previous 'dllimport' ignored}} >>> >>> extern int GlobalRedecl4; // >>> expected-note{{previous declaration is here}} >>> -__declspec(dllimport) extern int GlobalRedecl4; // >>> expected-error{{redeclaration of 'GlobalRedecl4' cannot add 'dllimport' >>> attribute}} >>> +__declspec(dllimport) extern int GlobalRedecl4; // >>> expected-warning{{redeclaration of 'GlobalRedecl4' should not add >>> 'dllimport' attribute}} >>> >>> // External linkage is required. >>> __declspec(dllimport) static int StaticGlobal; // >>> expected-error{{'StaticGlobal' must have external linkage when declared >>> 'dllimport'}} >>> @@ -224,10 +224,10 @@ __declspec(dllimport) void redecl3(); // >>> void redecl3() {} // expected-warning{{'redecl3' >>> redeclared without 'dllimport' attribute: previous 'dllimport' ignored}} >>> >>> void redecl4(); // expected-note{{previous >>> declaration is here}} >>> -__declspec(dllimport) void redecl4(); // expected-error{{redeclaration of >>> 'redecl4' cannot add 'dllimport' attribute}} >>> +__declspec(dllimport) void redecl4(); // expected-warning{{redeclaration >>> of 'redecl4' should not add 'dllimport' attribute}} >>> >>> void redecl5(); // expected-note{{previous >>> declaration is here}} >>> -__declspec(dllimport) inline void redecl5() {} // >>> expected-error{{redeclaration of 'redecl5' cannot add 'dllimport' >>> attribute}} >>> +__declspec(dllimport) inline void redecl5() {} // >>> expected-warning{{redeclaration of 'redecl5' should not add 'dllimport' >>> attribute}} >>> >>> // Friend functions >>> struct FuncFriend { >>> @@ -240,8 +240,8 @@ struct FuncFriend { >>> __declspec(dllimport) void friend1(); >>> void friend2(); // expected-warning{{'friend2' >>> redeclared without 'dllimport' attribute: previous 'dllimport' ignored}} >>> void friend3() {} // expected-warning{{'friend3' >>> redeclared without 'dllimport' attribute: previous 'dllimport' ignored}} >>> -__declspec(dllimport) void friend4(); // expected-error{{redeclaration of >>> 'friend4' cannot add 'dllimport' attribute}} >>> -__declspec(dllimport) inline void friend5() {} // >>> expected-error{{redeclaration of 'friend5' cannot add 'dllimport' >>> attribute}} >>> +__declspec(dllimport) void friend4(); // expected-warning{{redeclaration >>> of 'friend4' should not add 'dllimport' attribute}} >>> +__declspec(dllimport) inline void friend5() {} // >>> expected-warning{{redeclaration of 'friend5' should not add 'dllimport' >>> attribute}} >>> >>> void __declspec(dllimport) friend6(); // expected-note{{previous >>> declaration is here}} expected-note{{previous attribute is here}} >>> void __declspec(dllimport) friend7(); _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
