[ruby-core:109976] [Ruby master Bug#9760] mkmf does not allow for linking against custom libraries when a system library is present

[ruby-core:109976] [Ruby master Bug#9760] mkmf does not allow for linking against custom libraries when a system library is present

[rhenium (Kazuki Yamaguchi)]

Issue #9760 has been updated by rhenium (Kazuki Yamaguchi).


This is still an issue in the current master (e.g., https://github.com/ruby/openssl/issues/545).

If I understand correctly, mkmf.rb prepends libruby's path solely to prevent picking up a wrong libruby. Since the exact path of the correct libruby is known, I wonder if it's possible for mkmf.rb to just use it instead of the `-L[...] -lruby` combo to achieve the same thing.

BTW, Python 3.8 made an interesting change in https://bugs.python.org/issue21536: if the platform allows, extensions don't link to libpython (don't use `-lpythonX.Y`) and leave symbols unresolved until at runtime.

----------------------------------------
Bug #9760: mkmf does not allow for linking against custom libraries when a system library is present
https://bugs.ruby-lang.org/issues/9760#change-99226

* Author: zanegray (Andrew DeMaria)
* Status: Open
* Priority: Normal
* ruby -v: ruby 2.1.1p76 (2014-02-24 revision 45161) [x86_64-linux]
* Backport: 2.0.0: UNKNOWN, 2.1: REQUIRED, 2.2: REQUIRED
----------------------------------------
Hi,

Hopefully the title is not confusing, but the short story is that mkmf outputs a makefile that first searches the default lib path before searching any user provided lib paths. This is not an issue until one tries to link against an included library whose version is different than a preexisting system library.

The issue cropped up while trying to install the rugged gem (libgit2 wrapper) and a full dialog on the issue can be found on github https://github.com/libgit2/rugged/issues/351.

I was able to fix the issue with the attached patch (https://github.com/muff1nman/ruby/commit/a0c8bc32cfc11e61c5b9703bff243934c6509210)

---Files--------------------------------
fix_default_libpath.diff (1.2 KB)
early-libdir.patch (1.24 KB)


-- 
https://bugs.ruby-lang.org/