Unlike in C++03, a constant-expression is not an unevaluated operand in C++11.
Split out a new ExpressionEvaluationContext flag for this case, and don't treat
it as unevaluated in C++11. This fixes some crash-on-invalids where we would
allow references to class members in potentially-evaluated constant expressions
in static member functions, and also fixes half of PR10177.
The fix to PR10177 exposed a case where template instantiation failed to provide
a source location for a diagnostic, so TreeTransform has been tweaked to supply
source locations when transforming a type. The source location is still not very
good, but MarkDeclarationsReferencedInType would need to operate on a TypeLoc to
improve it further.
Also fix MarkDeclarationReferenced in C++98 mode to trigger instantiation for
static data members of class templates which are used in constant expressions.
This fixes a link-time problem, but we still incorrectly treat the member as
non-constant. The rest of the fix for that issue is blocked on PCH support for
early-instantiated static data members, which will be added in a subsequent
patch.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@146955 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index 6fc2dec..3619017 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -247,11 +247,12 @@
ExprResult Parser::ParseConstantExpression() {
- // C++ [basic.def.odr]p2:
+ // C++03 [basic.def.odr]p2:
// An expression is potentially evaluated unless it appears where an
// integral constant expression is required (see 5.19) [...].
+ // C++98 and C++11 have no such rule, but this is only a defect in C++98.
EnterExpressionEvaluationContext Unevaluated(Actions,
- Sema::Unevaluated);
+ Sema::ConstantEvaluated);
ExprResult LHS(ParseCastExpression(false));
return ParseRHSOfBinaryExpression(LHS, prec::Conditional);
@@ -1041,7 +1042,7 @@
if (T.expectAndConsume(diag::err_expected_lparen_after, "noexcept"))
return ExprError();
- // C++ [expr.unary.noexcept]p1:
+ // C++11 [expr.unary.noexcept]p1:
// The noexcept operator determines whether the evaluation of its operand,
// which is an unevaluated operand, can throw an exception.
EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated);
@@ -1439,8 +1440,8 @@
// [...] The operand is either an expression, which is an unevaluated
// operand (Clause 5) [...]
//
- // The GNU typeof and alignof extensions also behave as unevaluated
- // operands.
+ // The GNU typeof and GNU/C++11 alignof extensions also behave as
+ // unevaluated operands.
EnterExpressionEvaluationContext Unevaluated(Actions,
Sema::Unevaluated);
Operand = ParseCastExpression(true/*isUnaryExpression*/);
@@ -1456,8 +1457,8 @@
// [...] The operand is either an expression, which is an unevaluated
// operand (Clause 5) [...]
//
- // The GNU typeof and alignof extensions also behave as unevaluated
- // operands.
+ // The GNU typeof and GNU/C++11 alignof extensions also behave as
+ // unevaluated operands.
EnterExpressionEvaluationContext Unevaluated(Actions,
Sema::Unevaluated);
Operand = ParseParenExpression(ExprType, true/*stopIfCastExpr*/,