Sema: Respect -fdelayed-template-parsing when parsing constexpr functions
Functions declared as constexpr must have their parsing delayed in
-fdelayed-template-parsing mode so as not to upset later template
instantiation.
N.B. My reading of the standard makes it seem like delayed template
parsing is at odds with constexpr. We may want to make refinements in
other places in clang to make constexpr play nicer with this feature.
This fixes PR17334.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191484 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 10ed15a..a52ebf6 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -11010,7 +11010,8 @@
// However, they cannot be referenced if they are deleted, and they are
// deleted whenever the implicit definition of the special member would
// fail.
- if (!Func->isConstexpr() || Func->getBody())
+ if (!(Func->isConstexpr() && !getLangOpts().DelayedTemplateParsing) ||
+ Func->getBody())
return;
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Func);
if (!Func->isImplicitlyInstantiable() && (!MD || MD->isUserProvided()))
@@ -11101,13 +11102,14 @@
}
}
- if (!AlreadyInstantiated || Func->isConstexpr()) {
+ if (!AlreadyInstantiated ||
+ (Func->isConstexpr() && !getLangOpts().DelayedTemplateParsing)) {
if (isa<CXXRecordDecl>(Func->getDeclContext()) &&
cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass() &&
ActiveTemplateInstantiations.size())
PendingLocalImplicitInstantiations.push_back(
std::make_pair(Func, PointOfInstantiation));
- else if (Func->isConstexpr())
+ else if (Func->isConstexpr() && !getLangOpts().DelayedTemplateParsing)
// Do not defer instantiations of constexpr functions, to avoid the
// expression evaluator needing to call back into Sema if it sees a
// call to such a function.
diff --git a/test/Parser/DelayedTemplateParsing.cpp b/test/Parser/DelayedTemplateParsing.cpp
index 3e429d4..201fe1b 100644
--- a/test/Parser/DelayedTemplateParsing.cpp
+++ b/test/Parser/DelayedTemplateParsing.cpp
@@ -102,3 +102,15 @@
};
}
+namespace PR17334 {
+
+template <typename = void> struct ArrayRef {
+ constexpr ArrayRef() {}
+};
+template <typename = void> void CreateConstInBoundsGEP2_32() {
+ ArrayRef<> IdxList;
+}
+void LLVMBuildStructGEP() { CreateConstInBoundsGEP2_32(); }
+
+}
+