gecko-dev/build/build-clang/revert-r359260-due-to-bug41...

342 строки
12 KiB
Diff

https://llvm.org/pr41817 "The linkage changes in r359260 break MIDL code"
MIDL produces non-standards-compliant C code for some of our .idl files. MSVC
and older versions of clang-cl used to accept it, but r359260 inadvertently
caused such code to break. Until a fix is available upstream, let's revert
r359260 in the meantime.
Index: lib/AST/Decl.cpp
===================================================================
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -610,18 +610,6 @@
return LinkageInfo::external();
}
-static StorageClass getStorageClass(const Decl *D) {
- if (auto *TD = dyn_cast<TemplateDecl>(D))
- D = TD->getTemplatedDecl();
- if (D) {
- if (auto *VD = dyn_cast<VarDecl>(D))
- return VD->getStorageClass();
- if (auto *FD = dyn_cast<FunctionDecl>(D))
- return FD->getStorageClass();
- }
- return SC_None;
-}
-
LinkageInfo
LinkageComputer::getLVForNamespaceScopeDecl(const NamedDecl *D,
LVComputationKind computation,
@@ -633,28 +621,24 @@
// C++ [basic.link]p3:
// A name having namespace scope (3.3.6) has internal linkage if it
// is the name of
+ // - an object, reference, function or function template that is
+ // explicitly declared static; or,
+ // (This bullet corresponds to C99 6.2.2p3.)
+ if (const auto *Var = dyn_cast<VarDecl>(D)) {
+ // Explicitly declared static.
+ if (Var->getStorageClass() == SC_Static)
+ return getInternalLinkageFor(Var);
- if (getStorageClass(D->getCanonicalDecl()) == SC_Static) {
- // - a variable, variable template, function, or function template
- // that is explicitly declared static; or
- // (This bullet corresponds to C99 6.2.2p3.)
- return getInternalLinkageFor(D);
- }
-
- if (const auto *Var = dyn_cast<VarDecl>(D)) {
- // - a non-template variable of non-volatile const-qualified type, unless
- // - it is explicitly declared extern, or
- // - it is inline or exported, or
- // - it was previously declared and the prior declaration did not have
- // internal linkage
- // (There is no equivalent in C99.)
+ // - a non-inline, non-volatile object or reference that is explicitly
+ // declared const or constexpr and neither explicitly declared extern
+ // nor previously declared to have external linkage; or (there is no
+ // equivalent in C99)
+ // The C++ modules TS adds "non-exported" to this list.
if (Context.getLangOpts().CPlusPlus &&
Var->getType().isConstQualified() &&
!Var->getType().isVolatileQualified() &&
!Var->isInline() &&
- !isExportedFromModuleInterfaceUnit(Var) &&
- !isa<VarTemplateSpecializationDecl>(Var) &&
- !Var->getDescribedVarTemplate()) {
+ !isExportedFromModuleInterfaceUnit(Var)) {
const VarDecl *PrevVar = Var->getPreviousDecl();
if (PrevVar)
return getLVForDecl(PrevVar, computation);
@@ -674,6 +658,14 @@
if (PrevVar->getStorageClass() == SC_Static)
return getInternalLinkageFor(Var);
}
+ } else if (const FunctionDecl *Function = D->getAsFunction()) {
+ // C++ [temp]p4:
+ // A non-member function template can have internal linkage; any
+ // other template name shall have external linkage.
+
+ // Explicitly declared static.
+ if (Function->getCanonicalDecl()->getStorageClass() == SC_Static)
+ return getInternalLinkageFor(Function);
} else if (const auto *IFD = dyn_cast<IndirectFieldDecl>(D)) {
// - a data member of an anonymous union.
const VarDecl *VD = IFD->getVarDecl();
@@ -682,8 +674,6 @@
}
assert(!isa<FieldDecl>(D) && "Didn't expect a FieldDecl!");
- // FIXME: This gives internal linkage to names that should have no linkage
- // (those not covered by [basic.link]p6).
if (D->isInAnonymousNamespace()) {
const auto *Var = dyn_cast<VarDecl>(D);
const auto *Func = dyn_cast<FunctionDecl>(D);
@@ -743,20 +733,10 @@
// C++ [basic.link]p4:
- // A name having namespace scope that has not been given internal linkage
- // above and that is the name of
- // [...bullets...]
- // has its linkage determined as follows:
- // - if the enclosing namespace has internal linkage, the name has
- // internal linkage; [handled above]
- // - otherwise, if the declaration of the name is attached to a named
- // module and is not exported, the name has module linkage;
- // - otherwise, the name has external linkage.
- // LV is currently set up to handle the last two bullets.
+ // A name having namespace scope has external linkage if it is the
+ // name of
//
- // The bullets are:
-
- // - a variable; or
+ // - an object or reference, unless it has internal linkage; or
if (const auto *Var = dyn_cast<VarDecl>(D)) {
// GCC applies the following optimization to variables and static
// data members, but not to functions:
@@ -802,7 +782,7 @@
mergeTemplateLV(LV, spec, computation);
}
- // - a function; or
+ // - a function, unless it has internal linkage; or
} else if (const auto *Function = dyn_cast<FunctionDecl>(D)) {
// In theory, we can modify the function's LV by the LV of its
// type unless it has C linkage (see comment above about variables
@@ -856,8 +836,7 @@
mergeTemplateLV(LV, spec, computation);
}
- // FIXME: This is not part of the C++ standard any more.
- // - an enumerator belonging to an enumeration with external linkage; or
+ // - an enumerator belonging to an enumeration with external linkage;
} else if (isa<EnumConstantDecl>(D)) {
LinkageInfo EnumLV = getLVForDecl(cast<NamedDecl>(D->getDeclContext()),
computation);
@@ -865,7 +844,8 @@
return LinkageInfo::none();
LV.merge(EnumLV);
- // - a template
+ // - a template, unless it is a function template that has
+ // internal linkage (Clause 14);
} else if (const auto *temp = dyn_cast<TemplateDecl>(D)) {
bool considerVisibility = !hasExplicitVisibilityAlready(computation);
LinkageInfo tempLV =
@@ -872,9 +852,8 @@
getLVForTemplateParameterList(temp->getTemplateParameters(), computation);
LV.mergeMaybeWithVisibility(tempLV, considerVisibility);
- // An unnamed namespace or a namespace declared directly or indirectly
- // within an unnamed namespace has internal linkage. All other namespaces
- // have external linkage.
+ // - a namespace (7.3), unless it is declared within an unnamed
+ // namespace.
//
// We handled names in anonymous namespaces above.
} else if (isa<NamespaceDecl>(D)) {
Index: test/CXX/drs/dr23xx.cpp
===================================================================
--- a/clang/test/CXX/drs/dr23xx.cpp
+++ b/clang/test/CXX/drs/dr23xx.cpp
@@ -60,20 +60,3 @@
void wrong_value() { auto [x, y] = Bad2(); } // expected-error {{decomposes into 42 elements}}
} // namespace dr2386
#endif
-
-namespace dr2387 { // dr2387: 9
-#if __cplusplus >= 201402L
- template<int> int a = 0;
- extern template int a<0>; // ok
-
- template<int> static int b = 0;
- extern template int b<0>; // expected-error {{internal linkage}}
-
- template<int> const int c = 0;
- extern template const int c<0>; // ok, has external linkage despite 'const'
-
- template<typename T> T d = 0;
- extern template int d<int>;
- extern template const int d<const int>;
-#endif
-}
Index: test/CXX/module/module.interface/p3.cpp
===================================================================
--- a/clang/test/CXX/module/module.interface/p3.cpp
+++ b/clang/test/CXX/module/module.interface/p3.cpp
@@ -48,7 +48,7 @@
namespace { // expected-note {{here}}
export int d; // expected-error {{export declaration appears within anonymous namespace}}
}
-export template<typename> static int e; // expected-error {{declaration of 'e' with internal linkage cannot be exported}}
+export template<typename> static int e; // FIXME
export template<typename> static int f(); // expected-error {{declaration of 'f' with internal linkage cannot be exported}}
export const int k = 5;
export static union { int n; }; // expected-error {{declaration of 'n' with internal linkage cannot be exported}}
Index: test/CXX/module/module.interface/p5.cpp
===================================================================
--- a/clang/test/CXX/module/module.interface/p5.cpp
+++ b/clang/test/CXX/module/module.interface/p5.cpp
@@ -14,7 +14,7 @@
namespace NS {}
template<typename> int ta;
-template<typename> static int sta; // expected-note {{target}}
+template<typename> static int sta;
template<typename> void tb();
template<typename> static void stb(); // expected-note {{target}}
template<typename> struct tc {};
@@ -44,7 +44,7 @@
}
}
-export { // expected-note 19{{here}}
+export { // expected-note 18{{here}}
using ::a;
using ::sa; // expected-error {{using declaration referring to 'sa' with internal linkage}}
using ::b;
@@ -56,7 +56,7 @@
using ::sg1; // expected-error {{using declaration referring to 'sg1' with internal linkage}}
using ::ta;
- using ::sta; // expected-error {{using declaration referring to 'sta' with internal linkage}}
+ using ::sta; // FIXME {{using declaration referring to 'sta' with internal linkage}}
using ::tb;
using ::stb; // expected-error {{using declaration referring to 'stb' with internal linkage}}
using ::tc;
Index: test/CodeGenCXX/cxx1y-variable-template-linkage.cpp
===================================================================
--- a/clang/test/CodeGenCXX/cxx1y-variable-template-linkage.cpp
+++ b/clang/test/CodeGenCXX/cxx1y-variable-template-linkage.cpp
@@ -6,61 +6,21 @@
// should be 'internal global' and not 'linkonce_odr global'.
template <typename T> int x = 42;
-// CHECK-DAG: @_Z1xIiE = linkonce_odr global
+
// CHECK-DAG: @_Z1xIZL3foovE3FooE = internal global
-// 'static' affects the linkage of the global
-template <typename T> static int y = 42;
-// CHECK-DAG: @_ZL1yIiE = internal global
-// CHECK-DAG: @_ZL1yIZL3foovE3FooE = internal global
-
-// 'const' does not
-template <typename T> const int z = 42;
-// CHECK-DAG: @_Z1zIiE = linkonce_odr constant
-// CHECK-DAG: @_Z1zIZL3foovE3FooE = internal constant
-
-template <typename T> T t = 42;
-// CHECK-DAG: @_Z1tIiE = linkonce_odr global
-// CHECK-DAG: @_Z1tIKiE = linkonce_odr constant
-
-int mode;
-
// CHECK-DAG: define internal dereferenceable(4) i32* @_ZL3foov(
-static const int &foo() {
+static int &foo() {
struct Foo { };
-
- switch (mode) {
- case 0:
- // CHECK-DAG: @_Z1xIiE
- return x<int>;
- case 1:
- // CHECK-DAG: @_Z1xIZL3foovE3FooE
- return x<Foo>;
- case 2:
- // CHECK-DAG: @_ZL1yIiE
- return y<int>;
- case 3:
- // CHECK-DAG: @_ZL1yIZL3foovE3FooE
- return y<Foo>;
- case 4:
- // CHECK-DAG: @_Z1zIiE
- return z<int>;
- case 5:
- // CHECK-DAG: @_Z1zIZL3foovE3FooE
- return z<Foo>;
- case 6:
- // CHECK-DAG: @_Z1tIiE
- return t<int>;
- case 7:
- // CHECK-DAG: @_Z1tIKiE
- return t<const int>;
- }
+
+ // CHECK-DAG: ret i32* @_Z1xIZL3foovE3FooE
+ return x<Foo>;
}
#if !__has_feature(cxx_exceptions) // File A
// CHECKA-DAG: define dereferenceable(4) i32* @_Z3barv(
-const int &bar() {
+int &bar() {
// CHECKA-DAG: call dereferenceable(4) i32* @_ZL3foov()
return foo();
}
@@ -68,7 +28,7 @@
#else // File B
// CHECKB-DAG: declare dereferenceable(4) i32* @_Z3barv(
-const int &bar();
+int &bar();
int main() {
// CHECKB-DAG: call dereferenceable(4) i32* @_Z3barv()
Index: test/SemaCXX/warn-unused-filescoped.cpp
===================================================================
--- a/clang/test/SemaCXX/warn-unused-filescoped.cpp
+++ b/clang/test/SemaCXX/warn-unused-filescoped.cpp
@@ -207,9 +207,8 @@
namespace test10 {
#if __cplusplus >= 201103L
-// FIXME: Warn on template definitions with no instantiations?
template<class T>
-constexpr T pi = T(3.14);
+constexpr T pi = T(3.14); // expected-warning {{unused}}
#endif
}
Index: test/SemaCXX/warn-unused-variables.cpp
===================================================================
--- a/clang/test/SemaCXX/warn-unused-variables.cpp
+++ b/clang/test/SemaCXX/warn-unused-variables.cpp
@@ -135,9 +135,7 @@
template<typename T> int m = 0;
template<typename T> int m<T*> = 0;
- // This has external linkage, so could be referenced by a declaration in a
- // different translation unit.
- template<> const int m<void> = 0; // no warning
+ template<> const int m<void> = 0; // expected-warning {{unused variable}}
}
namespace ctor_with_cleanups {