misc/cgo/testgodefs: failing on linux-arm-arm5spacemonkey

[bcmills]

Now that #32407 is resolved, on to the next failure!

This one also appears to be due to the read-only GOROOT (#30316), so before proceeding I plan to see if I can fix that on the other linux builders.

##### ../misc/cgo/testgodefs
./test.bash: line 17: anonunion_defs.go: Permission denied
./test.bash: line 17: issue8478_defs.go: Permission denied
./test.bash: line 17: fieldtypedef_defs.go: Permission denied
# misc/cgo/testgodefs/testdata
./main.go:8:8: undefined: T
./main.go:12:10: undefined: Issue8478
2019/11/12 10:47:19 Failed: exit status 2
2019/11/12 10:47:25 FAILED

[mengzhuo]

I changed builder user to "gopher" after I saw the "run by root" message but it failed linux/mips64le too.
https://build.golang.org/log/fa1c19c15a7a5ddf418d576cb2a5ba4c375c54c0

However it's fine when I run them manually.

+ FILE_PREFIXES='anonunion issue8478 fieldtypedef'
+ cd testdata
+ RM=
+ for FP in '$FILE_PREFIXES'
+ go tool cgo -godefs -srcdir . anonunion.go
+ RM=' anonunion_defs.go'
+ for FP in '$FILE_PREFIXES'
+ go tool cgo -godefs -srcdir . issue8478.go
+ RM=' anonunion_defs.go issue8478_defs.go'
+ for FP in '$FILE_PREFIXES'
+ go tool cgo -godefs -srcdir . fieldtypedef.go
+ RM=' anonunion_defs.go issue8478_defs.go fieldtypedef_defs.go'
+ go build -o testgodefs .
+ ./testgodefs
+ EXIT=0
+ rm -rf _obj testgodefs anonunion_defs.go issue8478_defs.go fieldtypedef_defs.go
+ exit 0

[bcmills]

Yeah, there are currently some tests that fail with a read-only filesystem. I'm hoping to fix them this week.

[gopherbot]

Change https://golang.org/cl/206901 mentions this issue: misc/cgo/testgodefs: convert test from bash to Go