Comment 1:

Labels changed: added go1.3maybe.

Comment 2:

Labels changed: added release-none, removed go1.3maybe.

Comment 3:

Labels changed: added repo-main.

Comment 4:

This issue was updated by revision a1695d2.

Update issue #6688
R=iant, rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/55100044

Gentle ping @dvyukov @ianlancetaylor how are we doing here? Is this issue still a concern? Could I be of help here with your guidance?

This is still an issue. Fixing it will require wiping all dependencies on libc from race runtime. I've removed the main one -- on malloc/free -- some time ago, but there are still some minor ones.
If we eliminate dependency on libc/cgo, it will also allow using -race without enabling cgo, which would be nice as well.
But nobody actively complained about this as far as I know, so this was never high on my list.

Gotcha gotcha, thanks @dvyukov! Oh right, you opened #9918 which is still open.

If we eliminate dependency on libc/cgo, it will also allow using -race without enabling cgo, which would be nice as well.
But nobody actively complained about this as far as I know, so this was never high on my list.

In the meantime, many people actively complained about that issue :) Many (including me!) seem to want to build scratch-based Docker images with race-detector-enabled binaries copied from the previous Docker build stage.

What are minor things that are left?

What are errors when cgo is disabled for -race build?

If that check is commented out, it fails with:

runtime/race/internal/amd64v1(.text): relocation target getuid not defined
runtime/race/internal/amd64v1(.text): relocation target pthread_self not defined
runtime/race/internal/amd64v1(.text): relocation target abort not defined
runtime/race/internal/amd64v1(.text): relocation target mkdir not defined
runtime/race/internal/amd64v1(.text): relocation target isatty not defined
runtime/race/internal/amd64v1(.text): relocation target pthread_attr_getstack not defined
runtime/race/internal/amd64v1(.text): relocation target sigaction not defined
runtime/race/internal/amd64v1(.text): relocation target getrusage not defined
runtime/race/internal/amd64v1(.text): relocation target syslog not defined
runtime/race/internal/amd64v1(.text): relocation target getrlimit not defined
runtime/race/internal/amd64v1(.text): relocation target pipe not defined
runtime/race/internal/amd64v1(.text): relocation target sched_getaffinity not defined
runtime/race/internal/amd64v1(.text): relocation target __sched_cpucount not defined
runtime/race/internal/amd64v1(.text): relocation target pthread_attr_init not defined
runtime/race/internal/amd64v1(.text): relocation target pthread_getattr_np not defined
runtime/race/internal/amd64v1(.text): relocation target pthread_attr_destroy not defined
runtime/race/internal/amd64v1(.text): relocation target exit not defined
runtime/race/internal/amd64v1(.text): relocation target __errno_location not defined
runtime/race/internal/amd64v1(.text): relocation target setrlimit not defined
runtime/race/internal/amd64v1(.text): relocation target sysconf not defined
runtime/race/internal/amd64v1(.text): relocation target clock_gettime not defined
/go/pkg/tool/linux_amd64/link: too many errors

which looks similar to #9918 (comment)

To fix most of these one would need to add more ifdef's similar to this one:
https://github.com/llvm/llvm-project/blob/ca003ee06d0eac7e8facc179181298a05e4d03ed/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp#L152

I would assume most uses of these libc functions can be simply removed as not needed for the Go version (e.g. isatty/pthread_self).

Some may need to replaced with calls to internal analogs. E.g. for exit we have Die in sanitizer runtimes. Not sure why we ever need to call exit.

Few may be harder to remove. These need to be dealt on a case-by-case basis.

Once all of these are removed, we also need a test in llvm upstream to prevent introduction of new libc calls in future.
The test can be added here: https://github.com/llvm/llvm-project/blob/ca003ee06d0eac7e8facc179181298a05e4d03ed/compiler-rt/lib/tsan/go/buildgo.sh