~ach 2 years ago*

So my binaries with -lc are missing the _start symbol so just pick a random address then crash.

~ach 2 years ago

harec -o /run/user/1000/18e935ef9b76661c/temp.rt.0.ssa -N rt -t /home/ac/.cache/hare/rt/d9cd48a95d3312fe4cc7e40948de7e3b22a44e77f1f25a8e2e55649236dd72d7.td /home/ac/local/src/hare/stdlib/rt/+linux/+x86_64.ha /home/ac/local/src/hare/stdlib/rt/+linux/abort.ha /home/ac/local/src/hare/stdlib/rt/+linux/env.ha /home/ac/local/src/hare/stdlib/rt/+linux/errno.ha /home/ac/local/src/hare/stdlib/rt/+linux/platformstart+libc.ha /home/ac/local/src/hare/stdlib/rt/+linux/prctl.ha /home/ac/local/src/hare/stdlib/rt/+linux/segmalloc.ha /home/ac/local/src/hare/stdlib/rt/+linux/signal.ha /home/ac/local/src/hare/stdlib/rt/+linux/socket.ha /home/ac/local/src/hare/stdlib/rt/+linux/stat.ha /home/ac/local/src/hare/stdlib/rt/+linux/syscallno+x86_64.ha /home/ac/local/src/hare/stdlib/rt/+linux/syscalls.ha /home/ac/local/src/hare/stdlib/rt/+linux/types.ha /home/ac/local/src/hare/stdlib/rt/+x86_64/backtrace.ha /home/ac/local/src/hare/stdlib/rt/+x86_64/cpuid.ha /home/ac/local/src/hare/stdlib/rt/+x86_64/jmp.ha /home/ac/local/src/hare/stdlib/rt/abort.ha /home/ac/local/src/hare/stdlib/rt/ensure.ha /home/ac/local/src/hare/stdlib/rt/fenv_defs.ha /home/ac/local/src/hare/stdlib/rt/jmp.ha /home/ac/local/src/hare/stdlib/rt/malloc+libc.ha /home/ac/local/src/hare/stdlib/rt/memcpy.ha /home/ac/local/src/hare/stdlib/rt/memmove.ha /home/ac/local/src/hare/stdlib/rt/memset.ha /home/ac/local/src/hare/stdlib/rt/start+libc.ha /home/ac/local/src/hare/stdlib/rt/strcmp.ha 
qbe -o /run/user/1000/18e935ef9b76661c/temp.rt.1.s /run/user/1000/18e935ef9b76661c/temp.rt.0.ssa 
x86_64-unknown-linux-musl-as -g -o /run/user/1000/18e935ef9b76661c/temp.rt.2.o /run/user/1000/18e935ef9b76661c/temp.rt.1.s 
x86_64-unknown-linux-musl-as -g -o /run/user/1000/18e935ef9b76661c/temp.rt.3.o /home/ac/local/src/hare/stdlib/rt/+linux/syscall+x86_64.s 
x86_64-unknown-linux-musl-as -g -o /run/user/1000/18e935ef9b76661c/temp.rt.4.o /home/ac/local/src/hare/stdlib/rt/+x86_64/cpuid_native.s 
x86_64-unknown-linux-musl-as -g -o /run/user/1000/18e935ef9b76661c/temp.rt.5.o /home/ac/local/src/hare/stdlib/rt/+x86_64/fenv.s 
x86_64-unknown-linux-musl-as -g -o /run/user/1000/18e935ef9b76661c/temp.rt.6.o /home/ac/local/src/hare/stdlib/rt/+x86_64/getfp.s 
x86_64-unknown-linux-musl-as -g -o /run/user/1000/18e935ef9b76661c/temp.rt.7.o /home/ac/local/src/hare/stdlib/rt/+x86_64/longjmp.s 
x86_64-unknown-linux-musl-as -g -o /run/user/1000/18e935ef9b76661c/temp.rt.8.o /home/ac/local/src/hare/stdlib/rt/+x86_64/restore.s 
x86_64-unknown-linux-musl-as -g -o /run/user/1000/18e935ef9b76661c/temp.rt.9.o /home/ac/local/src/hare/stdlib/rt/+x86_64/setjmp.s 
x86_64-unknown-linux-musl-ar -csr /home/ac/.cache/hare/rt/d9cd48a95d3312fe4cc7e40948de7e3b22a44e77f1f25a8e2e55649236dd72d7.a /run/user/1000/18e935ef9b76661c/temp.rt.2.o /run/user/1000/18e935ef9b76661c/temp.rt.3.o /run/user/1000/18e935ef9b76661c/temp.rt.4.o /run/user/1000/18e935ef9b76661c/temp.rt.5.o /run/user/1000/18e935ef9b76661c/temp.rt.6.o /run/user/1000/18e935ef9b76661c/temp.rt.7.o /run/user/1000/18e935ef9b76661c/temp.rt.8.o /run/user/1000/18e935ef9b76661c/temp.rt.9.o 

The build driver is not picking up the assembly file containing the libc start symbol.

~ach 2 years ago

Ok after more digging, the program is being linked with ld, when it should be using $CC.

~ach 2 years ago*

Another reproduction of the issue with -v:

https://builds.sr.ht/~ach/job/757977

hare is clearly using the wrong linker despite the fact -lc is being passed. No crt.o files are being linked, hence the missing _start.

edit: sorry this build doesn't show the issue, my mistake, will post another.

~ach 2 years ago

I have resolved this issue - the problem was nixos setting LD to 'ld' which meant hare was using ld even when -lc was passed. The symptom of this is a successful link, but the _start symbol is missing. This manifests as a segfault.

~sircmpwn REPORTED NOT_OUR_BUG 2 years ago