Re: [gentoo-musl] What is crtbeginP.o ?

[Lei Zhang]

2016-06-10 17:15 GMT+08:00 Anthony G. Basile <blueness@g.o>:
> so i recommend you play with different gcc compiler profiles using
> gcc-config on the musl based system you built with GRS, and look at the
> collect2 line to see which end files are deployed with each setting.
> then i recommend trying to read the gcc spec file for each of the
> compiler profiles.  then if you know some assembly, look at the code for
> those end files which you can find in the musl source tree.  that'll
> give you some idea what's going on there.

Below are my findings after some experimentation:

crt files linked by default, on my glibc based host:
crt1.o crti.o crtn.o
crtbegin.o crtend.o

with "-static":
crt1.o crti.o crtn.o
crtbeginT.o crtend.o

with "-shared":
crti.o crtn.o
crtbeginS.o crtendS.o

This complies with what is written on this page:
https://dev.gentoo.org/~vapier/crt.txt

Things are a bit different on the musl based system. By default:
Scrt1.o crti.o crtn.o
crtbeginS.o crtendS.o

with "-static":
Scrt1.o crti.o crtn.o
crtbeginP.o crtendS.o

with "-shared":
crti.o crtn.o
crtbeginS.o crtendS.o

This looks like a bit of mess to me...

To make it even more confusing, I also found that on the glibc based
system, crtend.o and crtendS.o are the same; on the musl one,
crtbegin.o is the same as crtbeginT.o, and crtbeginP.o is the same as
crtbeginS.o.


Lei