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Bug
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Resolution: Won't Do
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Minor
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None
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None
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None
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None
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None
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rhel-sst-pt-gcc
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ssg_platform_tools
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3
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False
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No
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Red Hat Enterprise Linux
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None
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None
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None
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Unspecified Release Note Type - Unknown
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aarch64
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None
What were you trying to do that didn't work?
I am trying to analyze glibc's libc.so.6 using `objdump -d`. When a function passes a function (as a pointer) to another one, on x86_64 it shows the correct reference, but on aarch64 it does not.
An example - the function __spawni, from glibc:sysdeps/unix/sysv/linux/spawni.c:
/* Spawn a new process executing PATH with the attributes describes in *ATTRP. Before running the process perform the actions described in FILE-ACTIONS. */ int __spawni (pid_t * pid, const char *file, const posix_spawn_file_actions_t * acts, const posix_spawnattr_t * attrp, char *const argv[], char *const envp[], int xflags) { /* It uses __execvpex to avoid run ENOEXEC in non compatibility mode (it will be handled by maybe_script_execute). */ return __spawnix (pid, file, acts, attrp, argv, envp, xflags, xflags & SPAWN_XFLAGS_USE_PATH ? __execvpex :__execve); }
In x86_64, it correctly shows that this function references __execvpex and __execve:
$ objdump -d --prefix-addresses x86_64/libc.so.6 | grep '^[^ ]* <__spawni\>'
00000000000fc960 <__spawni> endbr64
00000000000fc964 <__spawni+0x4> sub $0x8,%rsp
00000000000fc968 <__spawni+0x8> lea -0x230ff(%rip),%r11 # 00000000000d9870 <execve>
00000000000fc96f <__spawni+0xf> lea -0x225f6(%rip),%rax # 00000000000da380 <__execvpex>
00000000000fc976 <__spawni+0x16> mov 0x10(%rsp),%r10d
00000000000fc97b <__spawni+0x1b> test $0x1,%r10b
00000000000fc97f <__spawni+0x1f> cmove %r11,%rax
00000000000fc983 <__spawni+0x23> push %rax
00000000000fc984 <__spawni+0x24> push %r10
00000000000fc986 <__spawni+0x26> callq 00000000000fc130 <__spawnix>
00000000000fc98b <__spawni+0x2b> add $0x18,%rsp
00000000000fc98f <__spawni+0x2f> retq
But on aarch64, it does not:
$ aarch64-linux-gnu-objdump -d --prefix-addresses aarch64/libc.so.6 | grep '^[^ ]* <__spawni\>' 00000000000db844 <__spawni> tst x6, #0x1 00000000000db848 <__spawni+0x4> adrp x8, 00000000000bb000 <__run_prefork_handlers+0x14c> 00000000000db84c <__spawni+0x8> adrp x7, 00000000000bb000 <__run_prefork_handlers+0x14c> 00000000000db850 <__spawni+0xc> add x8, x8, #0x1c0 00000000000db854 <__spawni+0x10> add x7, x7, #0xd00 00000000000db858 <__spawni+0x14> csel x7, x7, x8, ne // ne = any 00000000000db85c <__spawni+0x18> b 00000000000db1e0 <__spawnix>
Please provide the package NVR for which bug is seen:
Tried RHEL8/9/Fedora38/39/rawhide's binutils - several versions between 2.30 and 2.42.
How reproducible:
Always
Steps to reproduce
See above
Expected results
Both output correct references
Actual results
x86_64 does, aarch64 does not.
I personally tried only on x86_64, using aarch64-linux-gnu-objdump for the aarch64 binary. Someone tried for me the native objdump on aarch64 and the result was the same.
