reference to declaration through `sizeof` in initializer causes undeclared identifier

[MrBrN197]

Zig Version

0.16.0-dev.1204+389368392

Steps to Reproduce and Observed Behavior

typedef struct {} Object;

Object* alloc(int t) {
  return 0;
}

int main() {
   Object *ptr = alloc(sizeof(*ptr));
 }

zig translate-c src/test.c | zig ast-check

<stdin>:11:80: error: use of undeclared identifier 'ptr'
    var ptr: [*c]Object = alloc(@bitCast(@as(c_uint, @truncate(@sizeOf(@TypeOf(ptr.*))))));                                                                               ^~~

Expected Behavior

compile without errors

[steeve]

Tentative fix, which basically lets the sizeof to be of the type in case the expression is an identifier or a deref:

diff --git a/src/Translator.zig b/src/Translator.zig
index 2fa5b75..799f9d8 100644
--- a/src/Translator.zig
+++ b/src/Translator.zig
@@ -3752,11 +3752,14 @@ fn transTypeInfo(
     const operand = operand: {
         if (typeinfo.expr) |expr| {
             const operand = try t.transExpr(scope, expr, .used);
-            if (operand.tag() == .string_literal) {
-                const deref = try ZigTag.deref.create(t.arena, operand);
-                break :operand try ZigTag.typeof.create(t.arena, deref);
+            switch (operand.tag()) {
+                .string_literal => {
+                    const deref = try ZigTag.deref.create(t.arena, operand);
+                    break :operand try ZigTag.typeof.create(t.arena, deref);
+                },
+                .identifier, .deref => {},
+                else => break :operand try ZigTag.typeof.create(t.arena, operand),
             }
-            break :operand try ZigTag.typeof.create(t.arena, operand);
         }
         break :operand try t.transType(scope, typeinfo.operand_qt, typeinfo.op_tok);
     };

This fixes my test case at #238

[steeve]

In the case of OP, this generates the following Zig code:

pub const Object = extern struct {};
pub export fn alloc(arg_t: c_int) [*c]Object {
    var t = arg_t;
    _ = &t;
    return null;
}
pub export fn main() c_int {
    var ptr: [*c]Object = alloc(@bitCast(@as(c_uint, @truncate(@sizeOf(Object)))));
    _ = &ptr;
    return 0;
}