[!cgo] skip

env GOCACHE=$WORK/gocache  # Looking for compile flags, so need a clean cache.
[!windows] env PATH=.:$PATH
[!windows] chmod 0777 p/gcc p/clang
[!windows] exists p/gcc p/clang
[windows] exists p/gcc.bat p/clang.bat
! exists p/bug.txt
go build -x
! exists p/bug.txt

-- go.mod --
module m

-- m.go --
package m

import _ "m/p"

-- p/p.go --
package p

// #define X 1
import "C"

-- p/gcc --
#!/bin/sh
echo ran gcc >bug.txt
-- p/clang --
#!/bin/sh
echo ran clang >bug.txt
-- p/gcc.bat --
echo ran gcc >bug.txt
-- p/clang.bat --
echo ran clang >bug.txt