Emit the LC_BUILD_VERSION load command when creating a mach object. #13
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LC_BUILD_VERSION contains the min OS version on which this binary was built to run for its platform in mach object. It is required for targets like iOS Catalyst. Also, emit the __LLVM segment, __asm section to tell the Apple toolchain that this object is from assembler and has no bitcode. This trick is used in Kotlin/Native, Rust, Flutter, Golang and yasm.
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This patch was originally uploaded to the mailing list [1] but didn't have [1] https://lists.nasm.us/archives/nasm-devel/2021-July/000035.html |
When running with -fsanitize=leak enabled nasm prints this error:
==19965==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 360 byte(s) in 90 object(s) allocated from:
#0 0x7faee9396867 in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
netwide-assembler#1 0x5645d39a401c in nasm_malloc nasmlib/alloc.c:55
netwide-assembler#2 0x5645d3a41f9d in string_transform asm/strfunc.c:356
netwide-assembler#3 0x5645d3a37d40 in eval_strfunc asm/eval.c:761
netwide-assembler#4 0x5645d3a37d40 in expr6 asm/eval.c:906
netwide-assembler#5 0x5645d3a3968d in expr5 asm/eval.c:627
netwide-assembler#6 0x5645d3a39aca in expr4 asm/eval.c:602
netwide-assembler#7 0x5645d3a39b72 in expr3 asm/eval.c:563
netwide-assembler#8 0x5645d3a39db8 in expr2 asm/eval.c:537
netwide-assembler#9 0x5645d3a39f38 in expr1 asm/eval.c:511
netwide-assembler#10 0x5645d3a3a0b8 in expr0 asm/eval.c:485
netwide-assembler#11 0x5645d3a3a242 in rexp3 asm/eval.c:422
netwide-assembler#12 0x5645d3a3a508 in rexp2 asm/eval.c:396
netwide-assembler#13 0x5645d3a3a6a8 in rexp1 asm/eval.c:369
netwide-assembler#14 0x5645d3a3a838 in rexp0 asm/eval.c:342
netwide-assembler#15 0x5645d3a3a838 in cexpr asm/eval.c:305
netwide-assembler#16 0x5645d3a3ad08 in bexpr asm/eval.c:298
netwide-assembler#17 0x5645d3a3ad08 in evaluate asm/eval.c:1032
netwide-assembler#18 0x5645d39e4f20 in parse_line asm/parser.c:959
netwide-assembler#19 0x5645d399e243 in assemble_file asm/nasm.c:1735
netwide-assembler#20 0x5645d3998801 in main asm/nasm.c:719
netwide-assembler#21 0x7faee8aaed8f in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
netwide-assembler#22 0x7faee8aaee3f in __libc_start_main_impl ../csu/libc-start.c:392
netwide-assembler#23 0x5645d399acd4 in _start (/home/ivan/d/nasm/nasm+0x2e5cd4)
SUMMARY: AddressSanitizer: 360 byte(s) leaked in 90 allocation(s).
This problem is reproducible on test utf.asm.
The problem was caused by the fact that eval_strfunc doesn't free the string
allocated by string_transform.
When running with -fsanitize=leak enabled nasm prints this error:
==19965==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 360 byte(s) in 90 object(s) allocated from:
#0 0x7faee9396867 in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
netwide-assembler#1 0x5645d39a401c in nasm_malloc nasmlib/alloc.c:55
netwide-assembler#2 0x5645d3a41f9d in string_transform asm/strfunc.c:356
netwide-assembler#3 0x5645d3a37d40 in eval_strfunc asm/eval.c:761
netwide-assembler#4 0x5645d3a37d40 in expr6 asm/eval.c:906
netwide-assembler#5 0x5645d3a3968d in expr5 asm/eval.c:627
netwide-assembler#6 0x5645d3a39aca in expr4 asm/eval.c:602
netwide-assembler#7 0x5645d3a39b72 in expr3 asm/eval.c:563
netwide-assembler#8 0x5645d3a39db8 in expr2 asm/eval.c:537
netwide-assembler#9 0x5645d3a39f38 in expr1 asm/eval.c:511
netwide-assembler#10 0x5645d3a3a0b8 in expr0 asm/eval.c:485
netwide-assembler#11 0x5645d3a3a242 in rexp3 asm/eval.c:422
netwide-assembler#12 0x5645d3a3a508 in rexp2 asm/eval.c:396
netwide-assembler#13 0x5645d3a3a6a8 in rexp1 asm/eval.c:369
netwide-assembler#14 0x5645d3a3a838 in rexp0 asm/eval.c:342
netwide-assembler#15 0x5645d3a3a838 in cexpr asm/eval.c:305
netwide-assembler#16 0x5645d3a3ad08 in bexpr asm/eval.c:298
netwide-assembler#17 0x5645d3a3ad08 in evaluate asm/eval.c:1032
netwide-assembler#18 0x5645d39e4f20 in parse_line asm/parser.c:959
netwide-assembler#19 0x5645d399e243 in assemble_file asm/nasm.c:1735
netwide-assembler#20 0x5645d3998801 in main asm/nasm.c:719
netwide-assembler#21 0x7faee8aaed8f in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
netwide-assembler#22 0x7faee8aaee3f in __libc_start_main_impl ../csu/libc-start.c:392
netwide-assembler#23 0x5645d399acd4 in _start (/home/ivan/d/nasm/nasm+0x2e5cd4)
SUMMARY: AddressSanitizer: 360 byte(s) leaked in 90 allocation(s).
This problem is reproducible on test utf.asm.
The problem was caused by the fact that eval_strfunc doesn't free the string
allocated by string_transform.
Signed-off-by: Ivan Sorokin <[email protected]>
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FWIW, I'm also interested in getting this added. In Xcode 15.0, which was released recently, a brand-new linker is used, and this linker produces warnings like this, when linking nasm object files: Actually, when Xcode 12.0 was released ~3 years ago, that also produced a similar warning: In that case, I believe the warning went away in the next minor update - so I guess it's plausible it will go away this time away; but if not, we'd need an option like this. Yasm did implement something similar here: yasm/yasm@41762be However they control it via source directives, not command line options. I believe command line options are the better choice there, as they could be controlled in the same way as choosing between targeting macOS/iOS simulator etc. Yasm did choose to set macOS as default always, if nothing was chosen though. This avoids the linker warning when this matches the actual target, but produces hard errors instead of a soft warning if it turns out not to be the right choice. |
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I am also very much interested in getting this merged, for the same reason mentioned above by @mstorsjo. |
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PR not merged or responded after 4 years? That's a somewhat long turnaround time... It would be really nice to have this included. Thanks |
When running with -fsanitize=leak enabled nasm prints this error:
==19965==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 360 byte(s) in 90 object(s) allocated from:
#0 0x7faee9396867 in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
#1 0x5645d39a401c in nasm_malloc nasmlib/alloc.c:55
#2 0x5645d3a41f9d in string_transform asm/strfunc.c:356
#3 0x5645d3a37d40 in eval_strfunc asm/eval.c:761
#4 0x5645d3a37d40 in expr6 asm/eval.c:906
#5 0x5645d3a3968d in expr5 asm/eval.c:627
#6 0x5645d3a39aca in expr4 asm/eval.c:602
#7 0x5645d3a39b72 in expr3 asm/eval.c:563
#8 0x5645d3a39db8 in expr2 asm/eval.c:537
#9 0x5645d3a39f38 in expr1 asm/eval.c:511
#10 0x5645d3a3a0b8 in expr0 asm/eval.c:485
#11 0x5645d3a3a242 in rexp3 asm/eval.c:422
#12 0x5645d3a3a508 in rexp2 asm/eval.c:396
#13 0x5645d3a3a6a8 in rexp1 asm/eval.c:369
#14 0x5645d3a3a838 in rexp0 asm/eval.c:342
#15 0x5645d3a3a838 in cexpr asm/eval.c:305
#16 0x5645d3a3ad08 in bexpr asm/eval.c:298
#17 0x5645d3a3ad08 in evaluate asm/eval.c:1032
#18 0x5645d39e4f20 in parse_line asm/parser.c:959
#19 0x5645d399e243 in assemble_file asm/nasm.c:1735
#20 0x5645d3998801 in main asm/nasm.c:719
#21 0x7faee8aaed8f in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
#22 0x7faee8aaee3f in __libc_start_main_impl ../csu/libc-start.c:392
#23 0x5645d399acd4 in _start (/home/ivan/d/nasm/nasm+0x2e5cd4)
SUMMARY: AddressSanitizer: 360 byte(s) leaked in 90 allocation(s).
This problem is reproducible on test utf.asm.
The problem was caused by the fact that eval_strfunc doesn't free the string
allocated by string_transform.
Signed-off-by: Ivan Sorokin <[email protected]>
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@softworkz it wasn't until just a few weeks ago that we started using github. Somehow people submitted pull requests here anyway, that we never saw. |
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I would really much rather see this implemented as an output %pragma. Only allowing it on the command line really is not desirable, and if it is a %pragma then --pragma allows it on the command line, too. |
Ah, alright - that's the point that (probably) nobody knew :-) The other site looked kind of abandoned, I suppose,this let us think that GitHub is the place to go.. |
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Finally got a review after 4 years! :) Before modifying this PR, I’d like to clarify — is the mailing list no longer used for discussions and patch submissions? It seems that several PRs are being merged directly on GitHub, so I just want to make sure that’s the current process. |
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Yes, that is the current process. However, it turns out that this was already implemented as a %pragma and merged in NASM 3.00rc20, so this PR is redundant and can be closed. |
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Understood. It would’ve been nice to get at least a quick review or acknowledgment before closing — this patch was posted on both GitHub and the mailing list four years ago, and the recently added |
6 participants
LC_BUILD_VERSION contains the min OS version on which this binary
was built to run for its platform in mach object. It is required for
targets like iOS Catalyst.
Also, emit the __LLVM segment, __asm section to tell the Apple
toolchain that this object is from assembler and has no bitcode.
This trick is used in Kotlin/Native, Rust, Flutter, Golang and yasm.