Adriaan van Os wrote:
When producing Dwarf-2 debug-info, there are a number of additional failures
[p17:~/gpc/gpc-20070904/gcc-4.1.2-test] adriaan% make EXTRA_PFLAGS=-gdwarf-2 ... FAIL: aturbo3test.pas FAIL: crttest.pas FAIL: dialec3.pas FAIL: dialec5.pas FAIL: dialec6.pas FAIL: dialec7.pas ...
The backtrace is typically
Exception: EXC_BAD_ACCESS (0x0001) Codes: KERN_PROTECTION_FAILURE (0x0002) at 0x0000000c
Thread 0 Crashed: 0 cc1 0x00312eea decl_assembler_name + 16 (tree.c:257) 1 cc1 0x0036f529 machopic_output_function_base_name + 28 (darwin.c:251) 2 cc1 0x00170ba2 output_addr_const + 733 (final.c:3240) 3 cc1 0x00170b7c output_addr_const + 695 (final.c:3315) 4 cc1 0x00170a89 output_addr_const + 452 (final.c:3339) 5 cc1 0x00126242 dw2_asm_output_addr_rtx + 41 (dwarf2asm.c:220) 6 cc1 0x0012844b output_loc_sequence + 495 (dwarf2out.c:3230) 7 cc1 0x0013150f output_die + 678 (dwarf2out.c:7036) 8 cc1 0x00131411 output_die + 424 (dwarf2out.c:7159) 9 cc1 0x00131411 output_die + 424 (dwarf2out.c:7159) 10 cc1 0x00131411 output_die + 424 (dwarf2out.c:7159) 11 cc1 0x00131c71 output_comp_unit + 306 (dwarf2out.c:7230) 12 cc1 0x0013d09e dwarf2out_finish + 1120 (dwarf2out.c:14269) 13 cc1 0x00312212 toplev_main + 1947 (toplev.c:1030) 14 cc1 0x00001eda _start + 216 15 cc1 0x00001e01 start + 41
Thread 0 crashed with i386 Thread State: eax: 0x00000000 ebx: 0x00312ee7 ecx:0xa000bd00 edx: 0x4281fa7c edi: 0x00a07200 esi: 0x00000000 ebp:0xbfffd658 esp: 0xbfffd640 ss: 0x0000002f efl: 0x00010282 eip:0x00312eea cs: 0x00000027 ds: 0x0000002f es: 0x0000002f fs:0x00000000 gs: 0x00000037
But maybe the failures are Darwin-specific.
It seems that machopic_output_function_base_name tries to use
DECL_ASSEMBLER_NAME (current_function_decl)
however, at this time we are outside any function, so current_function_decl is NULL, and we get null pointer exception. Looking at output_addr_const I see that it uses assemble_name function which (via assemble_name_raw) uses ASM_OUTPUT_LABELREF. This macro calls machopic_output_function_base_name if the name is "<pic base>".
ATM I have no idea how this name could appear in expression outside a function, but clearly the details are Darwin specific.