Fix for PR4074: allow subscripting non-lvalue arrays in C90 mode.
I wasn't originally going to use this approach, but cases like
test/Sema/expr-comma.c make things difficult.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70096 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 873dd53..e789e54 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1621,13 +1621,11 @@
} else if (const PointerType *PTy = LHSTy->getAsPointerType()) {
BaseExpr = LHSExp;
IndexExpr = RHSExp;
- // FIXME: need to deal with const...
ResultType = PTy->getPointeeType();
} else if (const PointerType *PTy = RHSTy->getAsPointerType()) {
// Handle the uncommon case of "123[Ptr]".
BaseExpr = RHSExp;
IndexExpr = LHSExp;
- // FIXME: need to deal with const...
ResultType = PTy->getPointeeType();
} else if (const VectorType *VTy = LHSTy->getAsVectorType()) {
BaseExpr = LHSExp; // vectors: V[123]
@@ -1635,6 +1633,30 @@
// FIXME: need to deal with const...
ResultType = VTy->getElementType();
+ } else if (LHSTy->isArrayType()) {
+ // If we see an array that wasn't promoted by
+ // DefaultFunctionArrayConversion, it must be an array that
+ // wasn't promoted because of the C90 rule that doesn't
+ // allow promoting non-lvalue arrays. Warn, then
+ // force the promotion here.
+ Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) <<
+ LHSExp->getSourceRange();
+ ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy));
+ LHSTy = LHSExp->getType();
+
+ BaseExpr = LHSExp;
+ IndexExpr = RHSExp;
+ ResultType = LHSTy->getAsPointerType()->getPointeeType();
+ } else if (RHSTy->isArrayType()) {
+ // Same as previous, except for 123[f().a] case
+ Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) <<
+ RHSExp->getSourceRange();
+ ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy));
+ RHSTy = RHSExp->getType();
+
+ BaseExpr = RHSExp;
+ IndexExpr = LHSExp;
+ ResultType = RHSTy->getAsPointerType()->getPointeeType();
} else {
return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value)
<< LHSExp->getSourceRange() << RHSExp->getSourceRange());