Make library/header paths visible to cmd/go script tests, which is necessary for
cgo/gccgo tests to work correctly

diff --git a/src/cmd/go/script_test.go b/src/cmd/go/script_test.go
index dfaa40548e..9d0f0e9bcd 100644
--- a/src/cmd/go/script_test.go
+++ b/src/cmd/go/script_test.go
@@ -100,6 +100,10 @@ const (
 var extraEnvKeys = []string{
 	"SYSTEMROOT",         // must be preserved on Windows to find DLLs; golang.org/issue/25210
 	"WINDIR",             // must be preserved on Windows to be able to run PowerShell command; golang.org/issue/30711
+	"CPATH",
+	"C_INCLUDE_PATH",
+	"CPLUS_INCLUDE_PATH",
+	"LIBRARY_PATH",
 	"LD_LIBRARY_PATH",    // must be preserved on Unix systems to find shared libraries
 	"CC",                 // don't lose user settings when invoking cgo
 	"GO_TESTING_GOTOOLS", // for gccgo testing
szko-scripts'>koszko-scripts</option>
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<div class='path'>path: <a href='/guix/log/?id=81fe955acc5e7cc7a6a3fb96f0181fe187c7a189'>root</a>/<a href='/guix/log/tests?id=81fe955acc5e7cc7a6a3fb96f0181fe187c7a189'>tests</a>/<a href='/guix/log/tests/guix-git-authenticate.sh?id=81fe955acc5e7cc7a6a3fb96f0181fe187c7a189'>guix-git-authenticate.sh</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/guix-git-authenticate.sh?id=81fe955acc5e7cc7a6a3fb96f0181fe187c7a189&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-09-28 21:06:36 -0500'>2020-09-28</span></td><td><a href='/guix/commit/tests/guix-git-authenticate.sh?id=d8934360d2453a403b5433e71d09188e4ed23b57'>tests: Simplify shell exit status negation;</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/guix-archive.sh, tests/guix-build-branch.sh, tests/guix-build.sh,
tests/guix-daemon.sh, tests/guix-download.sh, tests/guix-environment.sh,
tests/guix-gc.sh, tests/guix-git-authenticate.sh, tests/guix-graph.sh,
tests/guix-hash.sh, tests/guix-lint.sh, tests/guix-pack-relocatable.sh,
tests/guix-pack.sh, tests/guix-package-aliases.sh, tests/guix-package-net.sh,
tests/guix-package.sh: Use the shell '!' keyword to negate command exit status
in place of 'if ...; then false; else true; fi'
</span></span></td><td>Eric Bavier</td></tr>
<tr><td><span title='2020-07-11 12:33:01 +0200'>2020-07-11</span></td><td><a href='/guix/commit/tests/guix-git-authenticate.sh?id=a98712785e0b042a290420fd74e5a4a5da4fc68f'>Add 'guix git authenticate'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/scripts/git.scm, guix/scripts/git/authenticate.scm,
tests/guix-git-authenticate.sh: New files.
* Makefile.am (MODULES): Add the *.scm files.
(SH_TESTS): Add 'tests/guix-git-authenticate.sh'.
* doc/guix.texi (Channels)[Specifying Channel Authorizations]: Mention
'guix git authenticate'.
(Invoking guix git authenticate): New node.
* po/guix/POTFILES.in: Add 'guix/scripts/git.scm' and
'guix/scripts/git/authenticate.scm'.
</span></span></td><td>Ludovic Courtès</td></tr>