[fpc-pascal] Crash on Windows for Aarch64 target

[Volo Zyko]

Hello,

Some time ago it was announced an experimental support for Windows on Aarch64 (namely in this post https://lists.freepascal.org/pipermail/fpc-pascal/2020-April/057762.html). I tried to build a dll with a proprietary code for that target. Building succeeded but it crashes on loading. At the moment I don't understand how to investigate the issue to provide more information about it.

Here is my setup (in case there are any obvious mistakes). I built FPC from source (using commit e091d263c84890f64ca8353fa837c4fd7eb94c37). Building on Windows was quite straightforward - make OS_TARGET=win64 CPU_TARGET=aarch64 BINUTILSPREFIX= OPT=-O- all (as it was described in the post above). There was one catch though. Since I used MSys I had to make sure that the path to existing FPC was earlier than MSys's paths, i.e. I did export PATH=/c/tools/FPC/3.2.2/bin/i386-Win32/fpc:$PATH. FPC build system doesn't understand MSys file paths which are produced by MSys make, one must use make from FPC distribution. After building I got ppcrossa64.exe which is PE32+ executable for x86-64 itself. After this I built my dll. The command line was roughly like this: /c/tools/FPC/3.3.1/bin/x86_64-win64/ppcrossa64 -O- -Twin64 -Paarch64 -Sd -CF64 -fPIC -XPaarch64-win64 -olib.dll lib.dpr.

Any help in investigating the crash would be appreciated. Obviously I cannot share the proprietary code (it's not mine). However, in case there are any tests from the FPC source code that I can build and run on ARM64 I would eagerly do it.

Volo.