[fpc-devel] NONE smart link broken on windows?

[Graeme Geldenhuys]

On Friday, 24 April 2026 23:57:16 BST Martin Frb via fpc-devel wrote:
> The code currently uses
>      tai_const.create_8bit(sizeof(pint))
> 
> But that can't be right when cross compiling?

Hi all,

I recently looked into whether sizeof(pint) in dbgdwarf.pas was producing 
incorrect DWARF address_size values during cross-compilation — specifically 
the concern that on a 64-bit host generating 32-bit debug info, sizeof(pint) 
would evaluate to 8 rather than 4.

The short answer is: it doesn't, and the code is correct as-is.

The reason I initially thought it might be a problem is the common assumption 
that sizeof(pint) reflects the host pointer size. That is true in user 
programs, but not for FPC's cross-compiler binaries. When ppcross386 is built, 
the compiler source is compiled with -dCPU_I386, which sets {$define CPU32}, 
which in turn causes PtrInt (= pint, Pascal being case-insensitive) to be 
defined as Longint — 4 bytes — regardless of the host architecture the binary 
runs on. So sizeof(pint) evaluates to the target pointer size at Pascal 
compile time, which is exactly what you want.

I verified this with a small test. Compiling a trivial program using 
ppcross386 on an x86_64 host with debug info:

----
program dwarftest;
var
  x: LongInt;
begin
  x := 42;
  WriteLn(x);
end.
----


$ ppcross386 -g -Cn dwarftest.pas
Free Pascal Compiler version 3.3.1 [2026/04/25] for i386
...

$ readelf --debug-dump=info dwarftest.o | grep -A5 "Compilation Unit"
  Compilation Unit @ offset 0:
   Length:        0x85 (32-bit)
   Version:       3
   Abbrev Offset: 0
   Pointer Size:  4

Pointer Size: 4 is correct for an i386 target. A patched build using 
voidpointertype.size produces identical output, confirming the two expressions 
are always equivalent.

I've closed the MR I had opened for this.

Graeme