Test errors on 32 bits system

[eclipseo]

Golang 1.12.6 on i686 and armv7:

Testing    in: /builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src
         PATH: /builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/sbin
       GOPATH: /builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build:/usr/share/gocode
  GO111MODULE: off
      command: go test -buildmode pie -compiler gc -ldflags "-X github.com/lightstep/lightstep-tracer-go/version=0.16.0 -extldflags '-Wl,-z,relro -Wl,--as-needed  -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld '"
      testing: github.com/lightstep/lightstep-tracer-go
github.com/lightstep/lightstep-tracer-go
Running Suite: LightstepTracerGo Suite
======================================
Random Seed: 1561930840
Will run 66 of 66 specs
• [MEASUREMENT]
Single Source GenSeededGUID should handle concurrency badly
/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/util_test.go:44
Ran 10 samples:
runtime:
  Fastest Time: 2.606s
  Slowest Time: 2.708s
  Average Time: 2.677s ± 0.030s
------------------------------
•
------------------------------
•! Panic in Spec Setup (JustBeforeEach) [0.001 seconds]
TracerImpl
/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:14
  Flush [JustBeforeEach]
  /builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:46
    when the client fails to translate the buffer
    /builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:47
      should emit an EventFlushError
      /builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:60
      Test Panicked
      runtime error: invalid memory address or nil pointer dereference
      /usr/lib/golang/src/runtime/panic.go:82
      Full Stack Trace
      	/usr/lib/golang/src/runtime/panic.go:522 +0x1ac
      github.com/lightstep/lightstep-tracer-go/lightstep/rand.(*Pool).Pick(...)
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/lightstep/rand/pool.go:57
      github.com/lightstep/lightstep-tracer-go.genSeededGUID(0xcf608278, 0xbf3e68fc)
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/util.go:26 +0x44
      github.com/lightstep/lightstep-tracer-go.NewTracer(0xb62a3f, 0xc, 0x0, 0x0, 0xb6d59e, 0x1c, 0x1bb, 0x0, 0x0, 0x0, ...)
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer.go:103 +0x264
      github.com/lightstep/lightstep-tracer-go.glob..func3.2()
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:42 +0x38
      github.com/onsi/ginkgo/internal/leafnodes.(*runner).runSync(0x1d61240, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/lightstep_tracer_go_suite_test.go:12 +0xb0
      testing.tRunner(0x1ccc500, 0xe19ee8)
      	/usr/lib/golang/src/testing/testing.go:865 +0xb0
      created by testing.(*T).Run
      	/usr/lib/golang/src/testing/testing.go:916 +0x2f0
      
------------------------------
•! Panic in Spec Setup (JustBeforeEach) [0.001 seconds]
TracerImpl
/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:14
  Flush [JustBeforeEach]
  /builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:46
    when the client fails to translate the buffer
BUILDSTDERR:     /builddir/build/BUIerror: Bad exit status from /var/tmp/rpm-tmp.iGdWFl (%check)
BUILDSTDERR:     Bad exit status from /var/tmp/rpm-tmp.iGdWFl (%check)
LD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:47
      should clear the flushing buffer
      /builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:70
      Test Panicked
      runtime error: invalid memory address or nil pointer dereference
      /usr/lib/golang/src/runtime/panic.go:82
      Full Stack Trace
      	/usr/lib/golang/src/runtime/panic.go:522 +0x1ac
      github.com/lightstep/lightstep-tracer-go/lightstep/rand.(*Pool).Pick(...)
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/lightstep/rand/pool.go:57
      github.com/lightstep/lightstep-tracer-go.genSeededGUID(0xcf74c0dd, 0xbf3e68fc)
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/util.go:26 +0x44
      github.com/lightstep/lightstep-tracer-go.NewTracer(0xb62a3f, 0xc, 0x0, 0x0, 0xb6d59e, 0x1c, 0x1bb, 0x0, 0x0, 0x0, ...)
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer.go:103 +0x264
      github.com/lightstep/lightstep-tracer-go.glob..func3.2()
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/tracer_impl_test.go:42 +0x38
      github.com/onsi/ginkgo/internal/leafnodes.(*runner).runSync(0x1d61240, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
      	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/lightstep_tracer_go_suite_test.go:12 +0xb0
      testing.tRunner(0x1ccc500, 0xe19ee8)
      	/usr/lib/golang/src/testing/testing.go:865 +0xb0
      created by testing.(*T).Run
      	/usr/lib/golang/src/testing/testing.go:916 +0x2f0
      
------------------------------
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x4 pc=0x602478]
goroutine 1103 [running]:
github.com/lightstep/lightstep-tracer-go/lightstep/rand.(*Pool).Pick(...)
	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/lightstep/rand/pool.go:57
github.com/lightstep/lightstep-tracer-go.genSeededGUID(0x1fc27c0, 0x0)
	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/util.go:26 +0x44
github.com/lightstep/lightstep-tracer-go.glob..func6.1.1(0xc350)
	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/util_test.go:77 +0x3c
created by github.com/lightstep/lightstep-tracer-go.glob..func6.1
	/builddir/build/BUILD/lightstep-tracer-go-0.16.0/_build/src/github.com/lightstep/lightstep-tracer-go/util_test.go:84 +0xd8
exit status 2
FAIL	github.com/lightstep/lightstep-tracer-go	26.860s