By default commands such as "ctest" would not look for certificates
at all: <https://issues.guix.gnu.org/issue/37371>.

This changes CMake such that commands honor SSL_CERT_FILE and SSL_CERT_DIR
as well as /etc/ssl/certs.

--- cmake-3.13.1/Source/cmCurl.cxx	2019-09-10 17:27:36.926907260 +0200
+++ cmake-3.13.1/Source/cmCurl.cxx	2019-09-10 17:52:35.475903919 +0200
@@ -2,11 +2,8 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmCurl.h"
 
-#if !defined(CMAKE_USE_SYSTEM_CURL) && !defined(_WIN32) &&                    \
-  !defined(__APPLE__) && !defined(CURL_CA_BUNDLE) && !defined(CURL_CA_PATH)
 #  define CMAKE_FIND_CAFILE
 #  include "cmSystemTools.h"
-#endif
 #include "cmStringAlgorithms.h"
 
 // curl versions before 7.21.5 did not provide this error code
@@ -30,6 +27,19 @@
     ::CURLcode res = ::curl_easy_setopt(curl, CURLOPT_CAINFO, cafile);
     check_curl_result(res, "Unable to set TLS/SSL Verify CAINFO: ");
   }
+
+  /* Honor the usual environment variables.  */
+  else if (cmSystemTools::GetEnv("SSL_CERT_FILE", e)) {
+    ::CURLcode res =
+      ::curl_easy_setopt(curl, CURLOPT_CAINFO, e.c_str());
+    check_curl_result(res, "Unable to set TLS/SSL Verify CAINFO: ");
+  }
+  else if (cmSystemTools::GetEnv("SSL_CERT_DIR", e)) {
+    ::CURLcode res =
+      ::curl_easy_setopt(curl, CURLOPT_CAPATH, e.c_str());
+    check_curl_result(res, "Unable to set TLS/SSL Verify CAINFO: ");
+  }
+
 #ifdef CMAKE_FIND_CAFILE
 #  define CMAKE_CAFILE_FEDORA "/etc/pki/tls/certs/ca-bundle.crt"
   else if (cmSystemTools::FileExists(CMAKE_CAFILE_FEDORA, true)) {
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<div class='path'>path: <a href='/guix/log/?id=0bcd1bc7780ad11c398def0717a24214e16bdc6a'>root</a>/<a href='/guix/log/gnu?id=0bcd1bc7780ad11c398def0717a24214e16bdc6a'>gnu</a>/<a href='/guix/log/gnu/packages?id=0bcd1bc7780ad11c398def0717a24214e16bdc6a'>packages</a>/<a href='/guix/log/gnu/packages/erlang.scm?id=0bcd1bc7780ad11c398def0717a24214e16bdc6a'>erlang.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/erlang.scm?id=0bcd1bc7780ad11c398def0717a24214e16bdc6a&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2018-08-16 05:32:47 +0200'>2018-08-16</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=666da84f0f54d3e2f1ab6b6c14ebd9899a47dd50'>gnu: erlang: Update to 21.0.5.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-08-16 05:21:38 +0200'>2018-08-16</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=70f57ae00525f6fc919f62aea647a33b29d28537'>gnu: Use ©.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-08-16 05:15:21 +0200'>2018-08-16</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=ed672882626d30d3e0deba6d9265ac4d321113f2'>gnu: erlang: Don't use unstable tarball.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-07-17 15:13:48 +0200'>2018-07-17</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=39eec9881d965060039a2b6bfbf545f06253161c'>gnu: erlang: Update to 21.0.</a><span class='msg-avail'>...</span></td><td>Nils Gillmann</td></tr>
<tr><td><span title='2018-06-12 07:44:05 +0100'>2018-06-12</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=b5453aa7c314bec95e0c25b904f3517d338577ed'>gnu: erlang: Patch occurrences of /bin/sh in the source.</a><span class='msg-avail'>...</span></td><td>Christopher Baines</td></tr>
<tr><td><span title='2018-06-12 07:43:59 +0100'>2018-06-12</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=9b25e1d1248da83fa3f39f8fe163b842ec4c4d5a'>gnu: erlang: Delete the bootstrap phase.</a><span class='msg-avail'>...</span></td><td>Christopher Baines</td></tr>
<tr><td><span title='2018-02-19 05:57:17 +0100'>2018-02-19</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=eae7ece1afee77fef8d3cdd3b65a208ead971fac'>gnu: erlang: Use HTTPS home page.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-02-16 11:11:41 +0100'>2018-02-16</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=1b0ce451f4ba492e72b7e1ee85534955664a6559'>gnu: erlang: Update phase style.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-02-16 11:11:41 +0100'>2018-02-16</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=629c1947ea2b007d7103612dc0d25237abb2b555'>gnu: erlang: Update to 20.2.3.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2017-12-13 19:51:00 -0500'>2017-12-13</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=35e86e3605fdfa9920749b2b791f799770722b14'>gnu: Erlang: Update to 20.1.7 [fixes CVE-2017-1000385].</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-12-04 10:36:48 +0100'>2017-12-04</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=8cbb58918c4e5fe236a1cf34ff46477f4932fb01'>gnu: erlang: Update to 20.1.</a><span class='msg-avail'>...</span></td><td>nee</td></tr>
<tr><td><span title='2017-10-20 22:55:51 +0200'>2017-10-20</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=fd75eb6cd4e5c689f9e6ce7dd8d87f423778d308'>gnu: Fix the hashes of mutated GitHub archives.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2017-09-04 00:10:59 -0400'>2017-09-04</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=d10092b849153dc27cfed0a9601fde6c7bdec918'>gnu: Put autoconf-related phases immediately after the 'unpack phase.</a><span class='msg-avail'>...</span></td><td>Kei Kebreau</td></tr>
<tr><td><span title='2017-07-31 17:02:36 +0200'>2017-07-31</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=ee217402f7bf4b9fd49250650cf94d882a5e1a23'>gnu: erlang: Update to 20.0.</a><span class='msg-avail'>...</span></td><td>Peter Mikkelsen</td></tr>
<tr><td><span title='2017-07-29 23:03:47 +0200'>2017-07-29</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=a4078acf4ab7d694e86ffcaef2073d71e58508f1'>gnu: erlang: Fix man-pages search path of 'erl -man'.</a><span class='msg-avail'>...</span></td><td>Peter Mikkelsen</td></tr>
<tr><td><span title='2017-05-06 15:50:56 +0200'>2017-05-06</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=5c4ea872247e38371ed9f9c3509ce566eee907b1'>gnu: erlang: Update to 19.3.</a><span class='msg-avail'>...</span></td><td>Pjotr Prins</td></tr>
<tr><td><span title='2016-06-24 10:45:26 -0400'>2016-06-24</span></td><td><a href='/guix/commit/gnu/packages/erlang.scm?id=3c6e42b3bc30371a333098e097efa033bbfd3afb'>gnu: Add erlang.</a><span class='msg-avail'>...</span></td><td>Steve Sprang</td></tr>