go_library fails to link shared library created by cc_binary

[robin-thomas]

Description

Currently, if any of the dependencies of go_library in cgo mode are not cc_library, objc_library, cc_proto_library or cc_import, it fails the build.

But in the case of external dependencies which are unable to use cc_library to bundle all its transitive dependencies (because of bazelbuild/bazel#492), they need to use cc_binary to create a *.so shared library.

Expected outcome

go_library should support linking shared libraries even if they are created by cc_binary.

Bazel version

0.20.0

OS version

Ubuntu 16.04

[jayconrod]

Are you able to use cc_import for this? I think that's supposed to be the tool to solve this problem.

For example, this works for me (but I'm not sure it's suitable for anything more than this trivial case):

load("@io_bazel_rules_go//go:def.bzl", "go_binary")

cc_binary(
    name = "libhello.so",
    srcs = ["hello.c"],
    linkshared = True,
)

cc_import(
    name = "hello",
    shared_library = ":libhello.so",
)

go_binary(
    name = "gello",
    srcs = ["gello.go"],
    cdeps = [":hello"],
    cgo = True,
)