gccgo: TestShared/tsan_shared fails with GCC 5.5.0 #24046
Description
Please answer these questions before submitting your issue. Thanks!
What version of Go are you using (go version)?
Go 1.10
Does this issue reproduce with the latest release?
Yes
What operating system and processor architecture are you using (go env)?
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/leo/.cache/go-build"
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/leo/go"
GORACE=""
GOROOT="/gnu/store/h4gwja8863p3jhkav8ja7s710acckzy1-go-1.10"
GOTMPDIR=""
GOTOOLDIR="/gnu/store/h4gwja8863p3jhkav8ja7s710acckzy1-go-1.10/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="/gnu/store/cfdn69spjc44x4sd0acrwhxq6yay3rbc-gcc-5.5.0/bin/gcc"
CXX="g++"
CGO_ENABLED="1"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build244943669=/tmp/go-build -gno-record-gcc-switches"
What did you do?
I am testing the update of Go from 1.9.4 to 1.10 in GNU Guix. We bootstrap from Go 1.4.3 using GCC 5.5.0. I invoke the build with sh all.bash.
What did you expect to see?
A successful compilation and test of Go 1.10, as with Go 1.9.4.
What did you see instead?
There is a test failure. If I understand correctly, GCC 5.5.0's ThreadSanitizer finds a race. When I rebuild Go 1.4.3 with GCC 6.4.0, and build Go 1.10 using that bootstrap Go and version of GCC, the race is not detected. The test fails consistently with GCC 5.5.0.
##### ../misc/cgo/testsanitizers
--- FAIL: TestShared (0.03s)
--- FAIL: TestShared/tsan_shared (2.54s)
cshared_test.go:71: `/tmp/guix-build-go-1.10.drv-0/TestShared367937240/tsan_shared` exited with exit status 66
==================
WARNING: ThreadSanitizer: data race (pid=28778)
Write of size 8 at 0x7ffff5495c30 by thread T1:
#0 pthread_attr_getstacksize <null> (tsan_shared+0x00000041be82)
#1 x_cgo_init <null> (libtsan_shared.so+0x00000008aeaf)
#2 runtime.rt0_go /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:199 (libtsan_shared.so+0x000000081586)
Previous write of size 8 at 0x7ffff5495c30 by main thread:
#0 <null> <null> (0x000000000001)
Location is stack of thread T1.
Thread T1 (tid=28786, running) created by main thread at:
#0 pthread_create <null> (tsan_shared+0x00000040c794)
#1 _cgo_try_pthread_create <null> (libtsan_shared.so+0x00000008ad70)
#2 x_cgo_sys_thread_create <null> (libtsan_shared.so+0x00000008ab12)
#3 _rt0_amd64_lib /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:56 (libtsan_shared.so+0x0000000813b6)
SUMMARY: ThreadSanitizer: data race ??:0 __interceptor_pthread_attr_getstacksize
==================
==================
WARNING: ThreadSanitizer: data race (pid=28778)
Read of size 8 at 0x7d080000dfe0 by thread T2:
#0 threadentry <null> (libtsan_shared.so+0x00000008b0d2)
Previous write of size 8 at 0x7d080000dfe0 by thread T1:
#0 malloc <null> (tsan_shared+0x00000040aba3)
#1 x_cgo_thread_start <null> (libtsan_shared.so+0x00000008b730)
#2 runtime.asmcgocall /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:718 (libtsan_shared.so+0x000000082fc6)
Location is heap block of size 24 at 0x7d080000dfe0 allocated by thread T1:
#0 malloc <null> (tsan_shared+0x00000040aba3)
#1 x_cgo_thread_start <null> (libtsan_shared.so+0x00000008b730)
#2 runtime.asmcgocall /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:718 (libtsan_shared.so+0x000000082fc6)
Thread T2 (tid=28791, running) created by thread T1 at:
#0 pthread_create <null> (tsan_shared+0x00000040c794)
#1 _cgo_try_pthread_create <null> (libtsan_shared.so+0x00000008ad70)
#2 _cgo_sys_thread_start <null> (libtsan_shared.so+0x00000008b011)
#3 x_cgo_thread_start <null> (libtsan_shared.so+0x00000008b7be)
#4 runtime.asmcgocall /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:718 (libtsan_shared.so+0x000000082fc6)
Thread T1 (tid=28786, running) created by main thread at:
#0 pthread_create <null> (tsan_shared+0x00000040c794)
#1 _cgo_try_pthread_create <null> (libtsan_shared.so+0x00000008ad70)
#2 x_cgo_sys_thread_create <null> (libtsan_shared.so+0x00000008ab12)
#3 _rt0_amd64_lib /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:56 (libtsan_shared.so+0x0000000813b6)
SUMMARY: ThreadSanitizer: data race ??:0 threadentry
==================
==================
WARNING: ThreadSanitizer: data race (pid=28778)
Read of size 8 at 0x7ffff7dd54f8 by thread T2:
#0 threadentry <null> (libtsan_shared.so+0x00000008b105)
Previous write of size 8 at 0x7ffff7dd54f8 by thread T1:
#0 x_cgo_init <null> (libtsan_shared.so+0x00000008ae43)
#1 runtime.rt0_go /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:199 (libtsan_shared.so+0x000000081586)
Location is global 'setg_gcc' of size 8 at 0x7ffff7dd54f8 (libtsan_shared.so+0x0000003134f8)
Thread T2 (tid=28791, running) created by thread T1 at:
#0 pthread_create <null> (tsan_shared+0x00000040c794)
#1 _cgo_try_pthread_create <null> (libtsan_shared.so+0x00000008ad70)
#2 _cgo_sys_thread_start <null> (libtsan_shared.so+0x00000008b011)
#3 x_cgo_thread_start <null> (libtsan_shared.so+0x00000008b7be)
#4 runtime.asmcgocall /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:718 (libtsan_shared.so+0x000000082fc6)
Thread T1 (tid=28786, running) created by main thread at:
#0 pthread_create <null> (tsan_shared+0x00000040c794)
#1 _cgo_try_pthread_create <null> (libtsan_shared.so+0x00000008ad70)
#2 x_cgo_sys_thread_create <null> (libtsan_shared.so+0x00000008ab12)
#3 _rt0_amd64_lib /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:56 (libtsan_shared.so+0x0000000813b6)
SUMMARY: ThreadSanitizer: data race ??:0 threadentry
==================
==================
WARNING: ThreadSanitizer: data race (pid=28778)
Read of size 8 at 0x7d080000df80 by thread T6:
#0 threadentry <null> (libtsan_shared.so+0x00000008b0d2)
Previous write of size 8 at 0x7d080000df80 by thread T1:
#0 malloc <null> (tsan_shared+0x00000040aba3)
#1 x_cgo_thread_start <null> (libtsan_shared.so+0x00000008b730)
#2 runtime.asmcgocall /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:688 (libtsan_shared.so+0x000000082f87)
Location is heap block of size 24 at 0x7d080000df80 allocated by thread T1:
#0 malloc <null> (tsan_shared+0x00000040aba3)
#1 x_cgo_thread_start <null> (libtsan_shared.so+0x00000008b730)
#2 runtime.asmcgocall /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:688 (libtsan_shared.so+0x000000082f87)
Thread T6 (tid=28796, running) created by thread T1 at:
#0 pthread_create <null> (tsan_shared+0x00000040c794)
#1 _cgo_try_pthread_create <null> (libtsan_shared.so+0x00000008ad70)
#2 _cgo_sys_thread_start <null> (libtsan_shared.so+0x00000008b011)
#3 x_cgo_thread_start <null> (libtsan_shared.so+0x00000008b7be)
#4 runtime.asmcgocall /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:688 (libtsan_shared.so+0x000000082f87)
Thread T1 (tid=28786, running) created by main thread at:
#0 pthread_create <null> (tsan_shared+0x00000040c794)
#1 _cgo_try_pthread_create <null> (libtsan_shared.so+0x00000008ad70)
#2 x_cgo_sys_thread_create <null> (libtsan_shared.so+0x00000008ab12)
#3 _rt0_amd64_lib /tmp/guix-build-go-1.10.drv-0/go/src/runtime/asm_amd64.s:56 (libtsan_shared.so+0x0000000813b6)
SUMMARY: ThreadSanitizer: data race ??:0 threadentry
==================
ThreadSanitizer: reported 4 warnings
FAIL
2018/02/22 05:28:09 Failed: exit status 1