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
ts'>koszko-scripts</option>
</select> <input type='submit' value='switch'/></form></td></tr>
<tr><td class='sub'>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
<table class='tabs'><tr><td>
<a href='/guix/about/'>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81'>refs</a><a class='active' href='/guix/log/gnu/packages/datamash.scm'>log</a><a href='/guix/tree/gnu/packages/datamash.scm?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81'>tree</a><a href='/guix/commit/gnu/packages/datamash.scm?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81'>commit</a><a href='/guix/diff/gnu/packages/datamash.scm?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/packages/datamash.scm'>
<input type='hidden' name='id' value='e0c6c18371e4b7029724471cf43d1c95b69d1b81'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81'>root</a>/<a href='/guix/log/gnu?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81'>gnu</a>/<a href='/guix/log/gnu/packages?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81'>packages</a>/<a href='/guix/log/gnu/packages/datamash.scm?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81'>datamash.scm</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/gnu/packages/datamash.scm?id=e0c6c18371e4b7029724471cf43d1c95b69d1b81&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-09-23 09:38:50 +0300'>2019-09-23</span></td><td><a href='/guix/commit/gnu/packages/datamash.scm?id=23cc2793e1b64c0d0218988fc76cf70f5ba8a612'>gnu: datamash: Update to 1.5.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/datamash.scm (datamash): Update to 1.5.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-12-23 16:37:51 +0200'>2018-12-23</span></td><td><a href='/guix/commit/gnu/packages/datamash.scm?id=b83ddd03d961ea0a0cf75eb6649ecec4fbd4fb94'>gnu: datamash: Update to 1.4.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/datamash.scm (datamash): Update to 1.4.
[source]: Remove patch.
* gnu/packages/patches/datamash-arm-tests.patch: Remove file.
* gnu/local.mk (dist_patch_DATA): Remove it.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-04-12 22:55:51 -0500'>2018-04-12</span></td><td><a href='/guix/commit/gnu/packages/datamash.scm?id=de7f234a3a3e583e7af832e956b44455c71dc5cb'>gnu: datamash: Fix tests on ARM systems.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/patches/datamash-arm-tests.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/datamash.scm (datamash)[source]: Use it.
</span></span></td><td>Eric Bavier</td></tr>
<tr><td><span title='2018-03-18 00:02:06 +0100'>2018-03-18</span></td><td><a href='/guix/commit/gnu/packages/datamash.scm?id=80f565d3137eceb479b8f7d39c26e00385dd65f6'>gnu: datamash: Update to 1.3.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/datamash.scm (datamash): Update to 1.3.
</span></span></td><td>Ludovic Courtès</td></tr>