https://sourceware.org/bugzilla/show_bug.cgi?id=28903
--- Comment #1 from John B Thiel <jbthiel at gmail dot com> --- Here are some notes from my FPC bug report, pulled forward for easy reference. I also put 2 linker maps in the other bug report, good-2.35.2 and bad-2.36.1, let me know if you need them attached again here. Will also supply other object files, maps, traces, etc. let me know if anything needed. === Minimal helloworld.pas generates faulty executable that immediately seg faults. GDB shows it breaks before main: (gdb) break main Breakpoint 1 at 0x401064 (gdb) run During startup program terminated with signal SIGSEGV, Segmentation fault. I have debugged some and it seems related to binutils-2.36.1 or binutils-libs. The problem also occurs with binutils-2.37. Reverting back to binutils-2.35.2 restores correct function, no segfault. === The linker maps I attached above are from default linker ld, which is ld.bfd. Now I tested 2 other linkers, by giving fpc -sh, then editing the ppas.sh to call a different linker, namely: ld.gold (also from binutils, same version as ld.bfd the default ld) ld.lld-12.0.1 Both these linkers give Segmentation Fault in the exe, on BOTH binutils-2.35.2 and 2.36.1. So only LD.BFD linker was working at all, and as of 2.36.1 it stopped working too. Note that LD.LLD is not in the binutils package, rather in sys-devel/lld. So the link problem seems to be at a deeper layer, not only binutils. The link.res shows there are only 3 input files: INPUT( /usr/local/fpc-2.6.4//lib/fpc/2.6.4/units/x86_64-linux/rtl/prt0.o myprog.o /usr/local/fpc-2.6.4//lib/fpc/2.6.4/units/x86_64-linux/rtl/system.o ) The prt0.o, system.o, are the stock ones from the binary Linux FPC264 distribution: 1712 Mar 3 2014 /usr/local/fpc-2.6.4//lib/fpc/2.6.4/units/x86_64-linux/rtl/prt0.o 361692 Mar 3 2014 /usr/local/fpc-2.6.4//lib/fpc/2.6.4/units/x86_64-linux/rtl/system.o Also, I briefly started examining objdump of the executables. It seems like (not sure yet), the correct startup code and entry point are present in the segfaulting exe. This suggests a problem with the startup trap used to jump there, or maybe some attributes of the code segment are not being set right. I have read elsewhere of evolving security initiatives with kernel changes, that are tightening requirements on the structure/permissions of executable code. -- You are receiving this mail because: You are on the CC list for the bug.
