unofficial mirror of bug-guix@gnu.org 
 help / color / mirror / code / Atom feed
* bug#37999: clang fails to pickup/supply startfiles to ld
@ 2019-10-30 20:48 Carl Dong
  2019-10-31  7:55 ` Mathieu Othacehe
                   ` (2 more replies)
  0 siblings, 3 replies; 9+ messages in thread
From: Carl Dong @ 2019-10-30 20:48 UTC (permalink / raw)
  To: 37999

Hi all,

Our clang toolchain seems to be quite broken at this time. In particular, it
fails to call `ld` in the right way such that the startfiles are picked up:

--8<---------------cut here---------------start------------->8---
$ guix environment --pure --container --ad-hoc clang@6 binutils -- clang++ -v -Xlinker --verbose
...
"/gnu/store/8aj9slzwi5vnmi5iszc5jh3hrvndj29c-profile/bin/ld"
	--eh-frame-hdr
	-m elf_x86_64
	-dynamic-linker /lib64/ld-linux-x86-64.so.2
	-o a.out
	crt1.o
	crti.o
	/gnu/store/64xzk1kwk30n7arqgmxs2qy7wzcnc8i3-gcc-7.4.0-lib/lib/gcc/x86_64-unknown-linux-gnu/7.4.0/crtbegin.o
	-L/gnu/store/64xzk1kwk30n7arqgmxs2qy7wzcnc8i3-gcc-7.4.0-lib/lib/gcc/x86_64-unknown-linux-gnu/7.4.0
	-L/gnu/store/64xzk1kwk30n7arqgmxs2qy7wzcnc8i3-gcc-7.4.0-lib/lib/gcc/x86_64-unknown-linux-gnu/7.4.0/../../..
	-L/gnu/store/zki2b9r9lkdxnb23sqc8xs99xs9s5x03-clang-6.0.1/bin/../lib
	--verbose
	-L/gnu/store/8aj9slzwi5vnmi5iszc5jh3hrvndj29c-profile/lib
	-lstdc++ -lm -lgcc_s -lgcc -lc -lgcc_s -lgcc
	/gnu/store/64xzk1kwk30n7arqgmxs2qy7wzcnc8i3-gcc-7.4.0-lib/lib/gcc/x86_64-unknown-linux-gnu/7.4.0/crtend.o
	crtn.o
...
attempt to open crt1.o failed
/gnu/store/8aj9slzwi5vnmi5iszc5jh3hrvndj29c-profile/bin/ld: cannot find crt1.o: No such file or directory
attempt to open crti.o failed
/gnu/store/8aj9slzwi5vnmi5iszc5jh3hrvndj29c-profile/bin/ld: cannot find crti.o: No such file or directory
...
attempt to open /gnu/store/64xzk1kwk30n7arqgmxs2qy7wzcnc8i3-gcc-7.4.0-lib/lib/gcc/x86_64-unknown-linux-gnu/7.4.0/libm.so failed
attempt to open /gnu/store/64xzk1kwk30n7arqgmxs2qy7wzcnc8i3-gcc-7.4.0-lib/lib/gcc/x86_64-unknown-linux-gnu/7.4.0/libm.a failed
attempt to open /gnu/store/64xzk1kwk30n7arqgmxs2qy7wzcnc8i3-gcc-7.4.0-lib/lib/gcc/x86_64-unknown-linux-gnu/7.4.0/../../../libm.so failed
attempt to open /gnu/store/64xzk1kwk30n7arqgmxs2qy7wzcnc8i3-gcc-7.4.0-lib/lib/gcc/x86_64-unknown-linux-gnu/7.4.0/../../../libm.a failed
attempt to open /gnu/store/zki2b9r9lkdxnb23sqc8xs99xs9s5x03-clang-6.0.1/bin/../lib/libm.so failed
attempt to open /gnu/store/zki2b9r9lkdxnb23sqc8xs99xs9s5x03-clang-6.0.1/bin/../lib/libm.a failed
attempt to open /gnu/store/8aj9slzwi5vnmi5iszc5jh3hrvndj29c-profile/lib/libm.so failed
attempt to open /gnu/store/8aj9slzwi5vnmi5iszc5jh3hrvndj29c-profile/lib/libm.a failed
attempt to open /gnu/store/mx2bgrpxkbdjsmhlxp9a30hbzcilk4cn-binutils-2.32/x86_64-unknown-linux-gnu/lib64/libm.so failed
attempt to open /gnu/store/mx2bgrpxkbdjsmhlxp9a30hbzcilk4cn-binutils-2.32/x86_64-unknown-linux-gnu/lib64/libm.a failed
attempt to open /no-ld-lib-path/libm.so failed
attempt to open /no-ld-lib-path/libm.a failed
attempt to open /gnu/store/mx2bgrpxkbdjsmhlxp9a30hbzcilk4cn-binutils-2.32/x86_64-unknown-linux-gnu/lib/libm.so failed
attempt to open /gnu/store/mx2bgrpxkbdjsmhlxp9a30hbzcilk4cn-binutils-2.32/x86_64-unknown-linux-gnu/lib/libm.a failed
/gnu/store/8aj9slzwi5vnmi5iszc5jh3hrvndj29c-profile/bin/ld: cannot find -lm
...
--8<---------------cut here---------------end--------------->8---

I believe this is because we have crt1.o, crti.o, and limb.so in the output of
our glibc package, which clang seems unaware of.

I don't know exactly how to fix this, but I did some digging in the clang
codebase (cfe-6.0.1 to be exact), and found that the crt1.o, crti.o arguments
are added in lib/Driver/ToolChains/Gnu.cpp.

These arguments are constructed using something like
Args.MakeArgString(ToolChain.GetFilePath("crti.o")), which really calls
Driver::GetFilePath in lib/Driver/Driver.cpp under the hood. Meaning that we
just need to make Driver::GetFilePath aware of our glibc path and return the
correct full path to crt1.o and crti.o.

If anyone can help out here it would be much appreciated.

Cheers,
Carl Dong
contact@carldong.me
"I fight for the users"

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2019-11-16 14:32 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-10-30 20:48 bug#37999: clang fails to pickup/supply startfiles to ld Carl Dong
2019-10-31  7:55 ` Mathieu Othacehe
2019-10-31 13:16 ` Bengt Richter
2019-10-31 14:11 ` Mathieu Othacehe
2019-10-31 22:57   ` Marius Bakke
2019-11-04 20:31     ` Carl Dong
2019-11-05  7:55       ` Mathieu Othacehe
2019-11-07 16:23         ` Danny Milosavljevic
2019-11-16 14:31         ` Mathieu Othacehe

Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/guix.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).