replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Parse: Disable delayed template parsing for constexpr functions 

Commit r191484 treated constexpr function templates as normal function
templates with respect to delaying their parsing.  However, this is
unnecessarily restrictive because there is no compatibility concern with
constexpr, MSVC doesn't support it.

Instead, simply disable delayed template parsing for constexpr function
templates.  This largely reverts the changes made in r191484 but keeps
it's unit test.

This fixes PR17661.

llvm-svn: 193274
This commit is contained in:
David Majnemer 2013-10-23 21:31:20 +00:00
parent a5ffd3f994
commit c85ed7e4a2
4 changed files with 14 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
clang/lib/Parse/ParseCXXInlineMethods.cpp
View File

@ -115,6 +115,7 @@ NamedDecl *Parser::ParseCXXInlineMethodDef(AccessSpecifier AS,
// the tokens and store them for parsing at the end of the translation unit.
if (getLangOpts().DelayedTemplateParsing &&
DefinitionKind == FDK_Definition &&
!D.getDeclSpec().isConstexprSpecified() &&
((Actions.CurContext->isDependentContext() ||
(TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate &&
TemplateInfo.Kind != ParsedTemplateInfo::ExplicitSpecialization)) &&

6
clang/lib/Parse/Parser.cpp
View File

@ -990,9 +990,9 @@ Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
// In delayed template parsing mode, for function template we consume the
// tokens and store them for late parsing at the end of the translation unit.
if (getLangOpts().DelayedTemplateParsing &&
Tok.isNot(tok::equal) &&
TemplateInfo.Kind == ParsedTemplateInfo::Template) {
if (getLangOpts().DelayedTemplateParsing && Tok.isNot(tok::equal) &&
TemplateInfo.Kind == ParsedTemplateInfo::Template &&
!D.getDeclSpec().isConstexprSpecified()) {
MultiTemplateParamsArg TemplateParameterLists(*TemplateInfo.TemplateParams);
ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);

8
clang/lib/Sema/SemaExpr.cpp
View File

@ -11088,8 +11088,7 @@ void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func) {
// 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() && !getLangOpts().DelayedTemplateParsing) ||
Func->getBody())
if (!Func->isConstexpr() || Func->getBody())
return;
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Func);
if (!Func->isImplicitlyInstantiable() && (!MD || MD->isUserProvided()))
@ -11180,14 +11179,13 @@ void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func) {
}
}
if (!AlreadyInstantiated ||
(Func->isConstexpr() && !getLangOpts().DelayedTemplateParsing)) {
if (!AlreadyInstantiated || Func->isConstexpr()) {
if (isa<CXXRecordDecl>(Func->getDeclContext()) &&
cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass() &&
ActiveTemplateInstantiations.size())
PendingLocalImplicitInstantiations.push_back(
std::make_pair(Func, PointOfInstantiation));
else if (Func->isConstexpr() && !getLangOpts().DelayedTemplateParsing)
else if (Func->isConstexpr())
// 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.

7
clang/test/Parser/DelayedTemplateParsing.cpp
View File

@ -114,3 +114,10 @@ void LLVMBuildStructGEP() { CreateConstInBoundsGEP2_32(); }
}
namespace PR17661 {
template <typename T>
constexpr T Fun(T A) { return T(0); }
constexpr int Var = Fun(20);
}