- Ignore const null check on deref in $defined and $sizeof #2633.

releasenotes.md

@@ -12,6 +12,7 @@
 - Optional does not play well with bit ops #2618.
 - `Bytebuffer.grow` was broken #2622.
 - Hex escapes like `"\x80"` would be incorrectly lowered. #2623
+- Ignore const null check on deref in `$defined` and `$sizeof` #2633.
 
 ### Stdlib changes
 - Add `ThreadPool` join function to wait for all threads to finish in the pool without destroying the threads.

src/compiler/sema_expr.c

@@ -6085,7 +6085,7 @@ TYPE_CALL:
 
 bool sema_expr_rewrite_insert_deref(SemaContext *context, Expr *original)
 {
-	if (expr_is_const_pointer(original) && !original->const_expr.ptr)
+	if (expr_is_const_pointer(original) && !original->const_expr.ptr && !context->call_env.in_no_eval)
 	{
 		RETURN_SEMA_ERROR(original, "This value is known to be null so you cannot dereference it.");
 	}

test/test_suite/compile_time_introspection/defined_null_deref_check.c3t

@@ -0,0 +1,10 @@
+module test;
+import std;
+
+fn int main()
+{
+	int x @if($defined((char*){}.is_digit()));
+	isz s = $sizeof((char*){}.is_digit());
+	$typeof((char*){}.is_digit()) t;
+	return 0;
+}