Implement C++17 P0386R2, inline variables. (The 'inline' specifier gives a
variable weak discardable linkage and partially-ordered initialization, and is
implied for constexpr static data members.)
llvm-svn: 273754
diff --git a/clang/lib/CodeGen/ItaniumCXXABI.cpp b/clang/lib/CodeGen/ItaniumCXXABI.cpp
index b33ef73..43d293a 100644
--- a/clang/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/clang/lib/CodeGen/ItaniumCXXABI.cpp
@@ -1905,10 +1905,18 @@
bool shouldPerformInit) {
CGBuilderTy &Builder = CGF.Builder;
- // We only need to use thread-safe statics for local non-TLS variables;
- // global initialization is always single-threaded.
+ // Inline variables that weren't instantiated from variable templates have
+ // partially-ordered initialization within their translation unit.
+ bool NonTemplateInline =
+ D.isInline() &&
+ !isTemplateInstantiation(D.getTemplateSpecializationKind());
+
+ // We only need to use thread-safe statics for local non-TLS variables and
+ // inline variables; other global initialization is always single-threaded
+ // or (through lazy dynamic loading in multiple threads) unsequenced.
bool threadsafe = getContext().getLangOpts().ThreadsafeStatics &&
- D.isLocalVarDecl() && !D.getTLSKind();
+ (D.isLocalVarDecl() || NonTemplateInline) &&
+ !D.getTLSKind();
// If we have a global variable with internal linkage and thread-safe statics
// are disabled, we can just let the guard variable be of type i8.
@@ -1962,7 +1970,11 @@
if (!D.isLocalVarDecl() && C &&
CGM.getTarget().getTriple().isOSBinFormatELF()) {
guard->setComdat(C);
- CGF.CurFn->setComdat(C);
+ // An inline variable's guard function is run from the per-TU
+ // initialization function, not via a dedicated global ctor function, so
+ // we can't put it in a comdat.
+ if (!NonTemplateInline)
+ CGF.CurFn->setComdat(C);
} else if (CGM.supportsCOMDAT() && guard->isWeakForLinker()) {
guard->setComdat(CGM.getModule().getOrInsertComdat(guard->getName()));
}