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> "DL libraries aren't really a different kind of library format (both |
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> static and shared libraries can be used as DL libraries);" |
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Library archives (.a) and shared objects (.so) differ in several ways. |
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Roughly speaking: |
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From a file format perspective, .a files are simple collections (man ar) |
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of independent compiled objects, while .so files are complete libraries |
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produced by the linker and contain additional information which tell the |
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dynamic linker (ld.so) how to load and share the code. |
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More importantly, code which is intended to be used in shared objects |
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must be compiled with specific options as position-independent code, |
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whereas code in an archive needs not. |
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You can't link dynamically against a library archive, so all DL code on |
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Linux must be compiled as a shared object, whether it's actually shared |
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or not (think plugins). |
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As for the static use-flag: don't use it, unless you have very good |
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reasons to do so. It will result in a system with larger binaries and in |
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many cases you will *not* get true statically-linked binaries (e.g. most |
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of the things which link against glibc). As for dynamic linking breakage |
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following upgrades, IMO portage and revdep-rebuild give good enough |
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support for fixing that. |
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andrea |
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