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How can I use gdb to debug code compiled using yasm?

I have build code using yasm and link to my C ++ program, but I cannot set breakpoints in gdb for characters from assembly language file.

The command lines are probably not very covered, but here we go:

"g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -fPIC -std=c++11 -I"$HOME/usr/include" -c -o "bin/gcc-4.7/debug/main.o" "main.cpp" yasm -g dwarf2 -f elf64 -o bin/gcc-4.7/debug/mandel.o mandel.yasm "g++" -L"$HOME/usr/lib" -Wl,-R -Wl,"$HOME/usr/lib" -Wl,-rpath-link -Wl,"$HOME/usr/lib" -o "bin/gcc-4.7/debug/mandel" -Wl,--start-group "bin/gcc-4.7/debug/main.o" "bin/gcc-4.7/debug/mandel.o" -Wl,-Bstatic -Wl,-Bdynamic -lboost_system -lboost_thread -Wl,--end-group -g

Everything is built without incident, and the program starts. But when I try to load it into gdb to debug it, I cannot put breakpoints on any functions in the yasm file. For example, I have a function called MandelRect. Here gdb shows me where he called from somewhere basically:

 (gdb) disassemble 0x404ada,0x404af0 Dump of assembler code from 0x404ada to 0x404af0: 0x0000000000404ada <main()+474>: mov %rax,%rdi 0x0000000000404add <main()+477>: callq 0x409980 <MandelRect> 0x0000000000404ae2 <main()+482>: movq $0x0,-0x18(%rbp) 0x0000000000404aea <main()+490>: jmp 0x404b1c <main()+540> 0x0000000000404aec <main()+492>: mov -0x18(%rbp),%rdx End of assembler dump.

Here gdb shows me that its address is:

 (gdb) info address MandelRect Symbol "MandelRect" is at 0x409980 in a file compiled without debugging.

Here gdb cannot set a breakpoint on it:

 (gdb) break MandelRect Function "MandelRect" not defined. Make breakpoint pending on future shared library load? (y or [n]) n

And if I put a breakpoint on the right address when the execution reaches this function, I will not be able to execute its instructions. It just works from tag to tag, as far as I can (fed up) say.

Obviously, maybe? - this is due to the fact that gdb insisted that the file was compiled without debugging. But in the corresponding .o file and in binary format, the characters appear:

 ~/tests/mandel/bin/gcc-4.7/debug% nm mandel.o | grep MandelRectAsm 0000000000000000 R MandelRectAsm ~/tests/mandel/bin/gcc-4.7/debug% nm mandel | grep MandelRectAsm 000000000040a340 R MandelRectAsm ~/tests/mandel/bin/gcc-4.7/debug% objdump -t mandel.o | grep -i MandelRectAsm 0000000000000000 g .txt 0000000000000000 MandelRectAsm ~/tests/mandel/bin/gcc-4.7/debug% objdump -t mandel | grep -i MandelRectAsm 000000000040a340 g .txt 0000000000000000 MandelRectAsm

So how can I fix this? Am I misunderstanding something or is yasm -g broken? Has anyone ever received debugging information from clarity for working with gdb?

( Linux 3.2.0-4-amd64 #1 SMP Debian 3.2.60-1+deb7u3 x86_64 GNU/Linux system Linux 3.2.0-4-amd64 #1 SMP Debian 3.2.60-1+deb7u3 x86_64 GNU/Linux .)

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c ++ linux yasm gdb dwarf
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1 answer

My program contained code that was outside the .text section, as I somehow managed to skip the "text" in the asm file (as you can see in the objdump output above). yasm allows you to name your sections as you wish, and obviously they end up being executable, but obviously many tools don't expect this ...

It also fixed some odd results that I got from perf .

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