samvv/bolt
1
0
Fork 0
Code Issues 24 Pull requests Projects Releases Packages Wiki Activity Actions

Prevent infinite loops when checking something like "foo".0.1.2

Browse source
This commit is contained in:
Sam Vervaeck 2024-01-21 01:56:01 +01:00
parent f2550e9430
commit a2701257dd
Signed by: samvv
SSH key fingerprint: SHA256:dIg0ywU1OP+ZYifrYxy8c5esO72cIKB+4/9wkZj1VaY
2 changed files with 26 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
bootstrap/cxx/include/bolt/Checker.hpp
View file

@ -265,7 +265,12 @@ namespace bolt {
*/
std::deque<class Constraint*> Queue;
void unify(Type* Left, Type* Right, Node* Source);
/**
* Unify two types, using `Source` as source location.
*
* \returns Whether a type variable was assigned a type or not.
*/
bool unify(Type* Left, Type* Right, Node* Source);
void solve(Constraint* Constraint);

25
bootstrap/cxx/src/Checker.cc
View file

@ -1294,8 +1294,18 @@ namespace bolt {
void Checker::solve(Constraint* Constraint) {
Queue.push_back(Constraint);
bool DidJoin = false;
std::deque<class Constraint*> NextQueue;
while (!Queue.empty()) {
while (true) {
if (Queue.empty()) {
if (NextQueue.empty() || !DidJoin) {
break;
}
DidJoin = false;
std::swap(Queue, NextQueue);
}
auto Constraint = Queue.front();
Queue.pop_front();
@ -1318,7 +1328,7 @@ namespace bolt {
unify(ElementTy, Field->FieldTy, Field->Source);
}
} else if (MaybeTuple->isVar()) {
// TODO Add logic for when tuple is a var
NextQueue.push_back(Constraint);
} else {
DE.add<NotATupleDiagnostic>(MaybeTuple, Field->Source);
}
@ -1337,7 +1347,9 @@ namespace bolt {
case ConstraintKind::Equal:
{
auto Equal = static_cast<CEqual*>(Constraint);
unify(Equal->Left, Equal->Right, Equal->Source);
if (unify(Equal->Left, Equal->Right, Equal->Source)) {
DidJoin = true;
}
break;
}
@ -1413,11 +1425,11 @@ namespace bolt {
Type* Right;
Node* Source;
// Internal state used by the unifier
ByteString CurrentFieldName;
TypePath LeftPath;
TypePath RightPath;
bool DidJoin = false;
Type* getLeft() const {
return Left;
@ -1525,6 +1537,8 @@ namespace bolt {
TV->set(Ty);
DidJoin = true;
propagateClasses(TV->asVar().Context, Ty);
// This is a very specific adjustment that is critical to the
@ -1826,10 +1840,11 @@ namespace bolt {
return false;
}
void Checker::unify(Type* Left, Type* Right, Node* Source) {
bool Checker::unify(Type* Left, Type* Right, Node* Source) {
// std::cerr << describe(C->Left) << " ~ " << describe(C->Right) << std::endl;
Unifier A { *this, Left, Right, Source };
A.unify();
return A.DidJoin;
}
}