Test failures on s390x

[eclipseo]

Test fails on s390x with Golang 1.12.6:

Testing    in: /builddir/build/BUILD/otto-15f95af6e78dcd2030d8195a138bd88d4f403546/_build/src
         PATH: /builddir/build/BUILD/otto-15f95af6e78dcd2030d8195a138bd88d4f403546/_build/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/sbin
       GOPATH: /builddir/build/BUILD/otto-15f95af6e78dcd2030d8195a138bd88d4f403546/_build:/usr/share/gocode
  GO111MODULE: off
      command: go test -buildmode pie -compiler gc -ldflags "-X github.com/robertkrimen/otto/version.commit=15f95af6e78dcd2030d8195a138bd88d4f403546 -X github.com/robertkrimen/otto/version=0 -extldflags '-Wl,-z,relro -Wl,--as-needed  -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld '"
      testing: github.com/robertkrimen/otto
github.com/robertkrimen/otto
~~~ FAIL: (Terst)
	math_test.go:107: 
		FAIL (==)
		     got: +Inf (float64)
		expected: -Inf (float64)
--- FAIL: TestMath_atan2 (0.00s)
~~~ FAIL: (Terst)
	runtime_test.go:594: 
		FAIL (==)
		     got: 1073741823 (int32)
		expected: -1073741824 (int)
--- FAIL: TestBinaryShiftOperation (0.00s)
FAIL
exit status 1
FAIL	github.com/robertkrimen/otto	1.748s

[stevenh]

32bit machine?

[stevenh]

This should be fixed by #474 if not please let me know.