`go run: cannot run non-main package` as Unprivileged User

I'm encountering an error with a recently-compiled golang compiler, but only as an unprivileged user. I'm hoping someone could provide advice on further troubleshooting ideas.

As root:

$ cd $HOME && pwd
/root
$ mkdir -pv $HOME/go/src/hello
/bin/mkdir: created directory 'go'
/bin/mkdir: created directory 'go/src'
/bin/mkdir: created directory 'go/src/hello'
$ cd go/src/hello
$ cat > hello.go << EOF
> package main
>
> import "fmt">
> func main() {
>   fmt.Printf("hello, world\n")
> }
> EOF
$ go build
$ ls
hello hello.go
$ ./hello
hello, world
$ go run hello.go
hello, world

As an unprivileged user:

$ cd $HOME && pwd
/usr/src/libcap
$ mkdir -pv $HOME/go/src/hello
/bin/mkdir: created directory 'go'
/bin/mkdir: created directory 'go/src'
/bin/mkdir: created directory 'go/src/hello'
$ cd go/src/hello
$ cat > hello.go << EOF
> package main
>
> import "fmt">
> func main() {
>   fmt.Printf("hello, world\n")
> }
> EOF
$ go build
can't load package: package libcap/go/src/hello: cannot find package "libcap/go/src/hello" in any of:
        /usr/src/libcap/go/src/hello (from $GOROOT)
        /usr/src/libcap/go/src/libcap/go/src/hello (from $GOPATH)
$ ls
hello.go
$ go run hello.go
go run: cannot run non-main package

System information:

$ go version
go version go1.12.2 gccgo (GCC) 9.2.0 linux/amd64

I'm running in an LFS chroot environment and first discovered the issue while compiling the libcap package, which contains a go module, in chapter 6.28 of the 20200119-systemd book. The host is a Debian live cd:

$ uname -a
Linux debian 4.19.0-6-amd64 #1 SMP Debian 4.19.67-2+deb10u1 (2019-09-20) x86_64 GNU/Linux

The go tests appear to be fairly nominal, with very few unexpected failures (command executed from gcc build directory):

$ ../contrib/test_summary | grep -A7 Summ > log
$ less log
...
          === go Summary ===

# of expected passes      7349
# of unexpected failures  1
# of expected failures    1
# of untested testcases   6
# of unsupported tests    1
/usr/src/gcc/gcc-9.2.0/build/gcc/gccgo  version 9.2.0 (GCC)
--
...
          === gotools Summary ===

# of expected passes      216
# of unexpected failures  4
# of untested testcases   159
/usr/src/gcc/gcc-9.2.0/build/./gcc/gccgo version 9.2.0  (GCC)
--
...
          === libgo Summary ===

# of expected passes      178
# of unexpected failures  6
/usr/src/gcc/gcc-9.2.0/build/./gcc/gccgo version 9.2.0  (GCC)
--
          === libgomp Summary ===

# of expected passes      6458
# of expected failures    2
# of unsupported tests    349
/usr/src/gcc/gcc-9.2.0/build/./gcc/gccgo version 9.2.0  (GCC)
--
...