search for: dummy_file

So I just got lua to link and run and work on x86-64 Linux with musl and lld. It did require one change to hack around incorrect handling of ELF weak aliases. In musl __stdio_exit.c <http://git.musl-libc.org/cgit/musl/tree/src/stdio/__stdio_exit.c> we have: static FILE *const dummy_file = 0; weak_alias(dummy_file, __stdin_used); weak_alias(dummy_file, __stdout_used); weak_alias(dummy_file, __stderr_used); weak_alias(old, new) is defined as: extern __typeof(old) new __attribute__((weak, alias(#old))) This generates the following object file: mspencer at mspencer-vm:~/Projects/tes...

...Does ELF support aliasing ? How is the relationship captured in ELF symbol table, that one symbol is a alias of another symbol ? > Note that __stdout_used is the last symbol in the .rodata section. > This means that the reader assigns the data (16 bytes of 0) to > __stdout_used. Because dummy_file and the other __stdx_used symbols > come before it, they end up in the right place in the final file. Did you change the Reader too ? The Reader doesnot allocate any space for __stdout_used. The size of the current symbol = (value of next symbol - current symbol). In this case its zero. >...

...and run and work on x86-64 Linux with musl > and lld. It did require one change to hack around incorrect handling > of ELF weak aliases. > > In musl __stdio_exit.c > <http://git.musl-libc.org/cgit/musl/tree/src/stdio/__stdio_exit.c> we > have: > > static FILE *const dummy_file = 0; > weak_alias(dummy_file, __stdin_used); > weak_alias(dummy_file, __stdout_used); > weak_alias(dummy_file, __stderr_used); > > weak_alias(old, new) is defined as: extern __typeof(old) new > __attribute__((weak, alias(#old))) > > This generates the following object file...

...l ? It is not explicitly captured. It's an implicit relationship due to the symbols having the same address. > >> Note that __stdout_used is the last symbol in the .rodata section. >> This means that the reader assigns the data (16 bytes of 0) to >> __stdout_used. Because dummy_file and the other __stdx_used symbols >> come before it, they end up in the right place in the final file. > > Did you change the Reader too ? No. I just made another symbol to steal the actual content. > > The Reader doesnot allocate any space for __stdout_used. The size of the &gt...

...ctory' remote::volume/directory ( woops, now remote::volume/directory continues to exist and contains an empty remote::volume/directory/directory :P ) # rsync -mr --delete 'directory' remote::volume (says "no files to transfer", and nothing happens. @#$%) # touch directory/dummy_file # rsync -mr --delete 'directory' remote::volume/directory ( vroom! now the contents of remote::volume/directory are being cleaned out. unfortunately remote::volume/directory/dummy_file will remain for all eternity.. ) What would be the closest approximation to something like this? # rsy...

...It's an implicit relationship due to > the symbols having the same address. Got it. > >> >>> Note that __stdout_used is the last symbol in the .rodata section. >>> This means that the reader assigns the data (16 bytes of 0) to >>> __stdout_used. Because dummy_file and the other __stdx_used symbols >>> come before it, they end up in the right place in the final file. >> >> Did you change the Reader too ? > > No. I just made another symbol to steal the actual content. We could change the Reader so that if the symbol is the last symbo...