ld error: section not found for address
I am on Mac OS X 10.6.5 with XCode 3.2.4 and trying to compile/port a code base which compiles successfully on 10.5. A file contains hand-coded assembly code for exception handling. The compile stops with a ld error saying section not found for address 0x... What does this error message mean?
I am new to Mac OS X programming, but my search through the web and docs hasn't turned up much. A related question would be what to look for in trying to fix it. Thanks.
I'll include some original code and explain what I tried.
.text
.align 1, 0x90
.globl _privateSnippetExecutorGeneral
_privateSnippetExecutorGeneral:
LFBg:
movl %esp,%ecx
pushl %ebp # proper stack frame needed for exception handling
LCFIg0:
movl %esp,%ebp
LCFIg1:
subl $0x8,%esp # padding + 32bit returnValue
pushl %esp # 32bit &returnValue
pushl %ecx # 32bit pCallStack
pushl %edx # 32bit nVtableOffset
pushl %eax # 32bit nFunctionIndex
call L_cpp_vtable_call$stub
movl 16(%esp),%eax # 32bit returnValue
leave
ret
LFEg:
.long .-_privateSnippetExecutorGeneral
There are 6 of the above assembly code blocks, virtually identical. I changed some 32-bit instructions to 64-bit counterparts and adjusted some stack manipulations. The call to L_cpp_vtable_call$stub is typical of the dynamic loader for 32-bit i386 operations. I've read docs from x86_64 and Apple but haven't seen a clear code sample of what it should be.
...
.section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support
EH_frame1:
.set L$set$frame1,LECIE1-LSCIE1
.long L$set$frame1 # length
LSCIE1:
.long 0 # CIE_ID
.byte 1 # version
.ascii "zPR\0" # augmentation
.byte 1 # code_alignment_factor (.uleb128 1)
.byte 0x7c # data_alignment_factor (.sleb128 -4)
.byte 8 # return_address_register
.byte 0x6 # augmentation size 7:
.byte 0x9b # ???
.long L___gxx_personality_v0$non_lazy_ptr-.
.byte 0x10
# initial_instructions:
.byte 0x0C # DW_CFA_def_cfa %esp, 4
.byte 5
.byte 4
.byte 0x88 # DW_CFA_offset ret, 1
.byte 1
.align 2
LECIE1:
Above is the CIE section. The gxx_personality_v0 line also follows the typical dynamic loader code example for setting up the default exception handling routine. I compiled a hello world program to see what gcc spits out, and I changed it to
.long ___gxx_personality_v0+4@GOTPCREL
...
.globl _privateSnippetExecutorGeneral.eh
_privateSnippetExecutorGeneral.eh:
LSFDEg:
.set L$set$g1,LEFDEg-LASFDEg
.long L$set$g1 # length
LASFDEg:
.long LASFDEg-EH_frame1 # CIE_pointer
.long LFBg-. # initial_location
.long LFEg-LFBg # address_range
.byte 0 # augmentation size 0
# instructions:
.byte 0x04 # DW_CFA_advance_loc4
.long LCFIg0-LFBg
.byte 0x0E # DW_CFA_def_cfa_offset 8
.byte 8
.byte 0x84 # DW_CFA_offset %ebp, 2
.byte 2
.byte 0x04 # DW_CFA_advance_loc4
.long LCFIg1-LCFIg0
.byte 0x0D # DW_CFA_def_cfa_register %ebp
.byte 4
.align 2
LEFDEg:
Then there are 6 FDE sections (as above) corresponding to the assembly blocks. I did not modify them.
...
.section __IMPORT,__jump_table,symbol_stubs,self_modifyi开发者_如何学运维ng_code+pure_instructions,5
L_cpp_vtable_call$stub:
.indirect_symbol _cpp_vtable_call
hlt ; hlt ; hlt ; hlt ; hlt
.section __IMPORT,__pointers,non_lazy_symbol_pointers
L___gxx_personality_v0$non_lazy_ptr:
.indirect_symbol ___gxx_personality_v0
.long 0
.constructor
.destructor
.align 1
.subsections_via_symbols
Finally the stub sections. I haven't found too many docs, but my understanding is these sections are invalid for x86_64. The calling convention for dynamic loading no longer requires stubs but uses the Global Offset Table (GOT). So I commented out these sections. Are there things I should/not be doing? Any docs you can point me to?
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