Body of `consteval` should be in an `ImmediateFunctionContext` instead of `ConstantEvaluated`.
PotentiallyEvaluated expressions in Immediate functions are in a `ImmediateFunctionContext` as well.
Fixes https://github.com/llvm/llvm-project/issues/51182
Original divergence: https://godbolt.org/z/vadGT5j6f
Differential Revision: https://reviews.llvm.org/D132659
- Class member variables are now in scope when parsing a ``requires`` clause. Fixes
`GH55216 <https://github.com/llvm/llvm-project/issues/55216>`_.
+- Correctly set expression evaluation context as 'immediate function context' in
+ consteval functions.
+ This fixes `GH51182 https://github.com/llvm/llvm-project/issues/51182`
C++2b Feature Support
bool isImmediateFunctionContext() const {
return Context == ExpressionEvaluationContext::ImmediateFunctionContext ||
(Context == ExpressionEvaluationContext::DiscardedStatement &&
+ InImmediateFunctionContext) ||
+ // C++2b [expr.const]p14:
+ // An expression or conversion is in an immediate function
+ // context if it is potentially evaluated and either:
+ // * its innermost enclosing non-block scope is a function
+ // parameter scope of an immediate function, or
+ // * its enclosing statement is enclosed by the compound-
+ // statement of a consteval if statement.
+ (Context == ExpressionEvaluationContext::PotentiallyEvaluated &&
InImmediateFunctionContext);
}
// Do not push if it is a lambda because one is already pushed when building
// the lambda in ActOnStartOfLambdaDefinition().
if (!isLambdaCallOperator(FD))
+ // [expr.const]/p14.1
+ // An expression or conversion is in an immediate function context if it is
+ // potentially evaluated and either: its innermost enclosing non-block scope
+ // is a function parameter scope of an immediate function.
PushExpressionEvaluationContext(
- FD->isConsteval() ? ExpressionEvaluationContext::ConstantEvaluated
+ FD->isConsteval() ? ExpressionEvaluationContext::ImmediateFunctionContext
: ExprEvalContexts.back().Context);
// Check for defining attributes before the check for redefinition.
if (auto *FD = dyn_cast<FunctionDecl>(E->getDecl()))
if (!isUnevaluatedContext() && !isConstantEvaluated() &&
- FD->isConsteval() && !RebuildingImmediateInvocation &&
- !FD->isDependentContext())
+ !isImmediateFunctionContext() && FD->isConsteval() &&
+ !RebuildingImmediateInvocation && !FD->isDependentContext())
ExprEvalContexts.back().ReferenceToConsteval.insert(E);
MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E, OdrUse,
RefsMinusAssignments);
return testDefaultArgForParam() + testDefaultArgForParam((E)1);
}
}
+
+namespace GH51182 {
+// Nested consteval function.
+consteval int f(int v) {
+ return v;
+}
+
+template <typename T>
+consteval int g(T a) {
+ // An immediate function context.
+ int n = f(a);
+ return n;
+}
+static_assert(g(100) == 100);
+// --------------------------------------
+template <typename T>
+consteval T max(const T& a, const T& b) {
+ return (a > b) ? a : b;
+}
+template <typename T>
+consteval T mid(const T& a, const T& b, const T& c) {
+ T m = max(max(a, b), c);
+ if (m == a)
+ return max(b, c);
+ if (m == b)
+ return max(a, c);
+ return max(a, b);
+}
+static_assert(max(1,2)==2);
+static_assert(mid(1,2,3)==2);
+} // namespace GH51182