C backend does not generate function pointer conversion

[ruihe774]

Zig Version

0.14.0-dev.2587+f57a7458b

Steps to Reproduce and Observed Behavior

A minimal example:

fn awd() void {}

pub fn main() void {
    @as(*const fn (u32) void, @ptrCast(&awd))(1);
}

Quoted from the generated non-compilable C code:

static void test_awd__224(void) {
 return;
}

static void test_main__225(void) {
 /* file:2:59 */
 test_awd__224(UINT32_C(1));
 return;
}

See also #22368 (comment)

Expected Behavior

The generated C code includes the function pointer conversion and can be compiled by C compiler.