Crash when trying to convert a struct slice to a vector #2039.

releasenotes.md

@@ -39,6 +39,7 @@
 - Atomic max was incorrect.
 - `"+".to_float()` would panic.
 - `import` can now both be @public and @norecurse.
+- Crash when trying to convert a struct slice to a vector #2039.
 
 ### Stdlib changes
 - `new_*` functions in general moved to version without `new_` prefix.

src/compiler/sema_casts.c

@@ -1045,16 +1045,21 @@ static bool rule_slice_to_vecarr(CastContext *cc, bool is_explicit, bool is_sile
 		if (is_silent) return false;
 		RETURN_CAST_ERROR(expr, "Zero sized slices can't be converted to arrays or vectors.");
 	}
+	Type *base = cc->from->array.base;
 	if (cc->to_group == CONV_ARRAY)
 	{
 		if (expr_is_const_string(expr) || expr_is_const_bytes(expr))
 		{
 			if (cc->to->array.len > size) size = cc->to->array.len;
 		}
-		cast_context_set_from(cc, type_get_array(cc->from->array.base, size));
+		cast_context_set_from(cc, type_get_array(base, size));
 	}
 	else
 	{
+		if (!type_is_valid_for_vector(base))
+		{
+			return report_cast_error(cc, false);
+		}
 		cast_context_set_from(cc, type_get_vector(cc->from->array.base, size));
 	}
 	return cast_is_allowed(cc, is_explicit, is_silent);

test/test_suite/vector/slice_to_vector_but_not_allowed_base.c3

@@ -0,0 +1,8 @@
+// Repro issue #2039
+module foo;
+struct Foo { void* x; }
+fn void main()
+{
+	Foo* foo;
+	float[<2>] a = foo[0..1]; // #error: It is not possible to cast
+}