Installing bash with rpath
Dear Bash developers, I am trying to build Bash for a relatively closed environment where I don't want the Bash executable to link with the system's libreadline and libncursesw, but my own installation of these libraries. However, even when I configure bash with `--enable-rpath', and add `-Wl,-rpath-link=$my_install/lib' to LDFLAGS, the bash executable doesn't have the absolute address of these libraries in it. As a result, the only way I can run my installation of Bash is to explicitly add `$my_install/lib' to LD_LIBRARY_PATH. I use the same recipe (to build Bash) for many other low-level GNU programs, but I don't have this problem for any other executable (they all contain the absolute address of the libraries they link with). I wanted to see if you have any recommendations to fix this problem. Thank you very much, Mohammad
Re: Installing bash with rpath
Thank you very much for the prompt reply, On 1/20/19 7:54 PM, Chet Ramey wrote: On 1/20/19 12:03 PM, Mohammad Akhlaghi wrote: Dear Bash developers, I am trying to build Bash for a relatively closed environment where I don't want the Bash executable to link with the system's libreadline and libncursesw, but my own installation of these libraries. However, even when I configure bash with `--enable-rpath', and add `-Wl,-rpath-link=$my_install/lib' to LDFLAGS, the bash executable doesn't have the absolute address of these libraries in it. Bash doesn't use --enable-rpath, and it's not in the list of options configure supports. Have you tried --with-installed-readline=path? And told the linker to use a specific directory for libraries using LDFLAGS when running the make? You are right about `--enable-rpath'. Since `--disable-rpath' existed, I assumed an `--enable-rpath' must also be present. Most programs only show one of the `--enable-FEATURE' or `--disable-FEATURE'. So, because my final bash executable didn't have any RPATH, I thought that `--enable-rpath' might also be present, but as you mentioned, it had no effect. Yes, I configure Bash using the `--with-installed-readline' and set LDFLAGS. It builds and installs successfully and there is no problem in that part. The problem is in running bash. I have installed Bash 5.0 and the respective libreadline and libncursesw in a non-standard directory (I don't have root access on the system). So, it will crash (because of not finding libreadline) unless I set LD_LIBRARY_PATH. I am trying to find a way to embed RPATH in the bash executable so I don't have to set LD_LIBRARY_PATH before calling bash (and thus inheriting this directory to everything that I call under bash). I would be grateful you could guide me on how I can configure Bash to have RPATH in its executable. Thank you very much, Mohammad
Re: Installing bash with rpath
On 1/21/19 12:25 AM, Chet Ramey wrote: Isn't there a linker option you can supply, possibly as part of LDFLAGS, to embed that into the bash binary? I pass `-Wl,-rpath-link=$instdir/lib' to LDFLAGS. It sets RPATH properly on all the programs I install (including libreadline, and many other basic programs), except for Bash and AWK. In my built programs, Bash and AWK are the only programs that depend on libreadline, but RPATH does get written into libreadline, so I don't know if the linking with libreadline has any affect on this problem or not. Is there any step in the build or install of Bash that somehow disables using this method of setting RPATH? So far I found this work-around: to manually write RPATH into the Bash executable after installation using patchelf: https://nixos.org/patchelf.html . But it would be much better/elegant if this manual intervention wouldn't be necessary. Thanks a lot, Mohammad
Re: Installing bash with rpath
On 1/22/19 2:25 PM, Chet Ramey wrot The bash link step doesn't do anything with rpath. The readline Makefiles set rpath to the installed location of the library at build time (using $libdir), so if you install it somewhere else that's going to be wrong. It should probably use $(DESTDIR)$(libdir) if that's what you use to install your copy of readline. Indeed, I don't modify the installation directory of readline and rpath works fine there. Is there any special reason that rpath isn't managed for Bash (similar to how its managed for readline)? Let me give some background on the cause of my problem and why I need to have rpath in Bash. I am an astrophysicist and maintainer of GNU Astronomy Utilities. In the sciences, we have a big problem of reproducibility: were research teams arrive at a result and publish it, but many don't know the versions of the programs they were using to get that result or how they were configured. As a result, many published research results are not reproducible. I am trying to tackle this problem in a "reproducible paper" project [1]. It builds all the necessary programs for a project (starting from Make and Bash and going all the way up to the higher-level science software used in a project and also an installation of TeX to enable creation of the paper in a closed environment also). It then runs those programs in the pre-defined order to get the exact same result, and finally builds the paper's PDF, using its internal build of LaTeX. Ofcourse, since many users use Mac, it has to also work on a Mac OS, so I don't currently build the C compiler or linker and rely on the host's low-level system libraries, compiler and linker. But above that, I try to keep everything. With the update of Bash and Readline 5.0 on my host operating system, I suddenly noticed that my build of Bash was crashing and after investigation I saw that it was actually linking to the readline installation on the host at run time, not to the readline within the project. I am currently using patchelf to add RPATH manually to the Bash executable. So I am really curious why RPATH isn't managed in Bash similar to how its managed in readline? Thanks a lot for all the great work on Bash and help and support, Cheers, Mohammad [1]: https://gitlab.com/makhlaghi/reproducible-paper/blob/pipeline/README-pipeline.md
Re: Installing bash with rpath
On 1/23/19 2:13 PM, Chet Ramey wrote: Is there any special reason that rpath isn't managed for Bash (similar to how its managed for readline)? Because bash, by default, links statically with its own copy of readline. If you want to do things differently, there is a mechanism: specify the --rpath option to the linker. I don't know why that's not working for you. It is indeed very strange, because I am using the same script to build both bash and readline, but rpath is written in one and ignored in the other. I'll look for a solution in my scripts then. Thanks a lot for the prompt help, Mohammad
