Skip to content

[clang] fix expression classification for dependent binary operators #159819

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Sep 19, 2025
Merged

[clang] fix expression classification for dependent binary operators #159819

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 7 additions & 0 deletions clang/lib/AST/ExprClassification.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -601,6 +601,13 @@ static Cl::Kinds ClassifyMemberExpr(ASTContext &Ctx, const MemberExpr *E) {
static Cl::Kinds ClassifyBinaryOp(ASTContext &Ctx, const BinaryOperator *E) {
assert(Ctx.getLangOpts().CPlusPlus &&
"This is only relevant for C++.");

// For binary operators which are unknown due to type dependence, the
// convention is to classify them as a prvalue. This does not matter much, but
// it needs to agree with how they are created.
if (E->getType() == Ctx.DependentTy)
return Cl::CL_PRValue;

// C++ [expr.ass]p1: All [...] return an lvalue referring to the left operand.
// Except we override this for writes to ObjC properties.
if (E->isAssignmentOp())
Expand Down
6 changes: 6 additions & 0 deletions clang/test/SemaTemplate/temp_arg_template.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -149,6 +149,12 @@ namespace CheckDependentNonTypeParamTypes {
};
// FIXME: This should be rejected, as there are no valid instantiations for E<char>::F
template struct E<char>;

#if __cplusplus >= 201703L
template<template<auto> class TT, class V> struct G {
using type = TT<((void)0, V::value)>;
};
#endif
}

namespace PR32185 {
Expand Down