gccrs: fix ICE in borrows to invalid expressions

We need to check if the borrowed value is valid before creating the
reference type. Otherwise this will lead to an ICE.

Fixes Rust-GCC#3140

gcc/rust/ChangeLog:

	* typecheck/rust-hir-type-check-expr.cc (TypeCheckExpr::visit): check for error
	* typecheck/rust-tyty-call.cc (TypeCheckCallExpr::visit): likewise and remove debug error

gcc/testsuite/ChangeLog:

	* rust/compile/issue-3046.rs: remove old error message
	* rust/compile/nr2/exclude: nr2 cant handle this
	* rust/compile/issue-3140.rs: New test.

Signed-off-by: Philip Herron <herron.philip@googlemail.com>

5 files changed, 33 insertions, 10 deletions

diff --git a/gcc/rust/typecheck/rust-hir-type-check-expr.cc b/gcc/rust/typecheck/rust-hir-type-check-expr.cc
index 7daa271..9a075c0 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-expr.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check-expr.cc
@@ -1366,6 +1366,8 @@ void
 TypeCheckExpr::visit (HIR::BorrowExpr &expr)
 {
   TyTy::BaseType *resolved_base = TypeCheckExpr::Resolve (expr.get_expr ());
+  if (resolved_base->is<TyTy::ErrorType> ())
+    return;
 
   // In Rust this is valid because of DST's
   //
diff --git a/gcc/rust/typecheck/rust-tyty-call.cc b/gcc/rust/typecheck/rust-tyty-call.cc
index dbb0379..75cf58f 100644
--- a/gcc/rust/typecheck/rust-tyty-call.cc
+++ b/gcc/rust/typecheck/rust-tyty-call.cc
@@ -140,13 +140,8 @@ TypeCheckCallExpr::visit (FnType &type)
     {
       location_t arg_locus = argument->get_locus ();
       auto argument_expr_tyty = Resolver::TypeCheckExpr::Resolve (*argument);
-      if (argument_expr_tyty->get_kind () == TyTy::TypeKind::ERROR)
-	{
-	  rust_error_at (
-	    argument->get_locus (),
-	    "failed to resolve type for argument expr in CallExpr");
-	  return;
-	}
+      if (argument_expr_tyty->is<TyTy::ErrorType> ())
+	return;
 
       // it might be a variadic function
       if (i < type.num_params ())
diff --git a/gcc/testsuite/rust/compile/issue-3046.rs b/gcc/testsuite/rust/compile/issue-3046.rs
index c982cc9..f0c72a3 100644
--- a/gcc/testsuite/rust/compile/issue-3046.rs
+++ b/gcc/testsuite/rust/compile/issue-3046.rs
@@ -12,12 +12,10 @@ fn test(v: LOption) -> Res {
     return Res::BAD;
 }
 
-
 fn main() {
     // Should be:
     // test(LOption::Some(2));
-    // 
+    //
     test(LOption(2));
     // { dg-error "expected function, tuple struct or tuple variant, found enum" "" { target *-*-* } .-1 }
-    // { dg-error "failed to resolve type for argument expr in CallExpr" "" { target *-*-* } .-2 }
 }
diff --git a/gcc/testsuite/rust/compile/issue-3140.rs b/gcc/testsuite/rust/compile/issue-3140.rs
new file mode 100644
index 0000000..dcf86db
--- /dev/null
+++ b/gcc/testsuite/rust/compile/issue-3140.rs
@@ -0,0 +1,27 @@
+enum State {
+    Succeeded,
+    Failed,
+}
+
+fn print_on_failure(state: &State) {
+    let mut num = 0;
+    match *state {
+        // error: expected unit struct, unit variant or constant, found tuple
+        //        variant `State::Failed`
+        State::Failed => {
+            num = 1;
+        }
+        State::Succeeded => {
+            num = 2;
+        }
+        _ => (),
+    }
+}
+
+fn main() {
+    let b = State::Failed(1);
+    // { dg-error "expected function, tuple struct or tuple variant, found struct .State." "" { target *-*-* } .-1 }
+
+    print_on_failure(&b);
+    // { dg-error "cannot find value .b. in this scope" "" { target *-*-* } .-1 }
+}
diff --git a/gcc/testsuite/rust/compile/nr2/exclude b/gcc/testsuite/rust/compile/nr2/exclude
index 945a697..e7344ed 100644
--- a/gcc/testsuite/rust/compile/nr2/exclude
+++ b/gcc/testsuite/rust/compile/nr2/exclude
@@ -195,4 +195,5 @@ issue-266.rs
 additional-trait-bounds2.rs
 auto_traits2.rs
 auto_traits3.rs
+issue-3140.rs
 # please don't delete the trailing newline