Function pointers don't work on Harvard architechture

[dukc]

Compile this with flags -betterC -mtriple=avr -mcpu=atmega328p --gcc=avr-gcc --Xcc=-mmcu=atmega328p

void function() fPtr;

extern(C) void main()
{   fPtr = {fPtr = null;};
}

Results in (stack trace omitted):

Invalid bitcast
void ()* bitcast (void () addrspace(1)* @_D5delay4mainUZ9__lambda1FNbNiNfZv to void ()*)
in function main
LLVM ERROR: Broken function found, compilation aborted!

Tested version 1.30.0.

[kinke]

Fixed by #4465.