squiid/llvm
1
0
Fork 0
Code Issues Pull requests Activity

[flang] Fix a crash when an array constructor contains an unlimited polymorphic value

Browse source 
Summary:
C7113 States that "An ac-value shall not be unlimited polymorphic."  We failed
to detect this situation which resulted in a crash when trying to get the
underlying derived type specification of the unlimited polymorphic value.

I added code to avoid the crash, code to emit an error message, and a test.

Reviewers: klausler, tskeith, DavidTruby

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83793
This commit is contained in:
Pete Steinfeld 2020-07-14 10:08:34 -07:00
parent bef00b244c
commit 0c64cb6d08
2 changed files with 29 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

15
flang/lib/Semantics/expression.cpp
View file

@ -1159,8 +1159,12 @@ public:
template <typename T> Result Test() {
if (type_ && type_->category() == T::category) {
if constexpr (T::category == TypeCategory::Derived) {
return AsMaybeExpr(ArrayConstructor<T>{
type_->GetDerivedTypeSpec(), MakeSpecific<T>(std::move(values_))});
if (type_->IsUnlimitedPolymorphic()) {
return std::nullopt;
} else {
return AsMaybeExpr(ArrayConstructor<T>{type_->GetDerivedTypeSpec(),
MakeSpecific<T>(std::move(values_))});
}
} else if (type_->kind() == T::kind) {
if constexpr (T::category == TypeCategory::Character) {
if (auto len{type_->LEN()}) {
@ -1295,6 +1299,13 @@ void ArrayConstructorContext::Add(const parser::AcValue &x) {
auto restorer{exprAnalyzer_.GetContextualMessages().SetLocation(
expr.value().source)};
if (MaybeExpr v{exprAnalyzer_.Analyze(expr.value())}) {
if (auto exprType{v->GetType()}) {
if (exprType->IsUnlimitedPolymorphic()) {
exprAnalyzer_.Say(
"Cannot have an unlimited polymorphic value in an "
"array constructor"_err_en_US);
}
}
Push(std::move(*v));
}
},

16
flang/test/Semantics/resolve70.f90
View file

@ -57,3 +57,19 @@ subroutine s1()
!ERROR: Non-extensible derived type 'inextensible' may not be used with CLASS keyword
class(inextensible), allocatable :: x
end subroutine s1
subroutine s2()
type t
integer i
end type t
type, extends(t) :: t2
real x
end type t2
contains
function f1(dummy)
class(*) dummy
type(t) f1(1)
!ERROR: Cannot have an unlimited polymorphic value in an array constructor
f1 = [ (dummy) ]
end function f1
end subroutine s2