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0 pointsdalias12y ago0 comments

LD_PRELOAD alone wouldn't do it because glibc's dynamic linker is closely tied to glibc. In particular thread-local storage requires close cooperation between them. Likewise, musl needs its own dynamic linker.

What could be done in theory is replacing /lib/ld-linux.so.2 with a symlink to musl. One of the long-term goals for musl is for this to actually work, at least for many programs. But right now there are a lot of glibc-specific symbols that get pulled in magically by glibc's headers, even when the program at the source-level is 100% portable code, and we don't have coverage for all of these.

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throwawayaway12y ago· 1 in thread

Excellent response! I have a program that spends 10% of it's time in vfprintf for string processing, and I really think the program should not be spending that much time/any time there. I looked at the libc6 vfprintf implementation and it's pretty esoteric looking stuff. It might be worth my time using your library or something similar to swap it out.

justincormack12y ago

Musl has the benefit of being very readable, and you can just use bits of code if you like due to the license.

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