translate-c segfaults on typedef'd pointer subtraction

[phase]

Zig Version

0.11.0-dev.1568+c9b957c93

Steps to Reproduce and Observed Behavior

Using zig translate-c, I get a segfault with this case:

typedef char* S;
void foo() {
    S a, b;
    long c = a - b;
}

Looks like it has something to do with this typedef. If a and b are char*, this translates correctly.

Expected Behavior

Valid compilation or error saying why it failed

[Vexu]

Stack trace:

thread 4256 panic: attempt to use null value
/home/vexu/Documents/zig/zig/src/translate_c.zig:1751:64: 0x8d3f4bf in transBinaryOperator (zig)
        const elem_type = lhs_qt_translated.castTag(.c_pointer).?.data.elem_type;
                                                               ^
/home/vexu/Documents/zig/zig/src/translate_c.zig:1293:70: 0x8a9e7cb in transStmt (zig)
        .BinaryOperatorClass => return transBinaryOperator(c, scope, @ptrCast(*const clang.BinaryOperator, stmt), result_used),
                                                                     ^