[Pkg-pascal-devel] Bug#830906: freepascal textmode IDE crashes on startup on arm64

[peter green]

Package: fp-ide-3.0.0
Severity: important

The freepascal textmode IDE crashes on startup on arm64. I rebuilt it 
with debug symbols enabled and got the following backtrace.

root at pine64pro:/# gdb /fpc-3.0.0+dfsg/fpcsrc/ide/bin/aarch64-linux/fp
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Reading symbols from /fpc-3.0.0+dfsg/fpcsrc/ide/bin/aarch64-linux/fp...done.
(gdb) run
Starting program: /fpc-3.0.0+dfsg/fpcsrc/ide/bin/aarch64-linux/fp

Program received signal SIGSEGV, Segmentation fault.
0x000000000043851c in REGISTERTYPE (S=...) at 
rtl-extra/src/inc/objects.pp:2935
2935         Do P := P^.Next;                                 { Find end 
of chain }
(gdb) p P
$1 = 0x0
(gdb) bt
#0  0x000000000043851c in REGISTERTYPE (S=...)
     at rtl-extra/src/inc/objects.pp:2935
#1  0x00000000006d1f4c in REGISTERTIMEDDIALOG () at fv/src/timeddlg.pas:246
#2  0x00000000006d1f6c in TIMEDDLG_$$_init () at fv/src/timeddlg.pas:252
#3  0x000000000041a4cc in fpc_initializeunits () at ../inc/system.inc:895
#4  0x0000000000400888 in main () at fp.pas:350
(gdb) p S
$2 = {OBJTYPE = 98, VMTLINK = 0x8872f8, LOAD = 0x6d1ae8, STORE = 0x6d1c58,
   NEXT = 0x0}
(gdb)

Not sure what is going wrong here.  gdb tells me that P is nil and yet 
there is a gaurd against that in the code. Maybe a miscompilation of 
some sort?

The issue does not seem to appear with upstream trunk.