As for libc's `system', change Awk to look for `sh' in $PATH.  This patch is
only meant to be used during bootstrapping, where we don't know in advance the
absolute file name of `sh'.

--- gawk-4.1.3/io.c	2015-05-19 15:37:20.000000000 +0200
+++ gawk-4.1.3/io.c	2015-06-09 18:39:36.918414881 +0200
@@ -2025,7 +2025,7 @@
 
 		set_sigpipe_to_default();
 
-		execl("/bin/sh", "sh", "-c", command, NULL);
+		execlp("sh", "sh", "-c", command, NULL);
 		_exit(errno == ENOENT ? 127 : 126);
 
 	case -1:
@@ -2077,7 +2077,7 @@
 
 		signal(SIGPIPE, SIG_DFL);
 
-		execl("/bin/sh", "sh", "-c", command, NULL);
+		execlp("sh", "sh", "-c", command, NULL);
 		_exit(errno == ENOENT ? 127 : 126);
 
 	case -1:
@@ -2422,7 +2422,7 @@
 			fatal(_("close of pipe failed (%s)"), strerror(errno));
 		/* stderr does NOT get dup'ed onto child's stdout */
 		set_sigpipe_to_default();
-		execl("/bin/sh", "sh", "-c", str, NULL);
+		execlp("sh", "sh", "-c", str, NULL);
 		_exit(errno == ENOENT ? 127 : 126);
 	}
 #endif /* NOT __EMX__, NOT __MINGW32__ */
@@ -2659,7 +2659,7 @@
 		if (close(p[0]) == -1 || close(p[1]) == -1)
 			fatal(_("close of pipe failed (%s)"), strerror(errno));
 		set_sigpipe_to_default();
-		execl("/bin/sh", "sh", "-c", cmd, NULL);
+		execlp("sh", "sh", "-c", cmd, NULL);
 		_exit(errno == ENOENT ? 127 : 126);
 	}
 #endif /* NOT __EMX__, NOT __MINGW32__ */
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<div class='path'>path: <a href='/guix/log/?id=3f09b05d8d402d306105ef5ac63f8b6dc49c5e3a&amp;showmsg=1'>root</a>/<a href='/guix/log/gnu.scm?id=3f09b05d8d402d306105ef5ac63f8b6dc49c5e3a&amp;showmsg=1'>gnu.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.scm?id=3f09b05d8d402d306105ef5ac63f8b6dc49c5e3a'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2020-07-25 19:11:37 +0200'>2020-07-25</span></td><td class='logsubject'><a href='/guix/commit/gnu.scm?id=d51bfe242fbe6f3f8f71d723e8fe0c7bbe711ba1'>Use 'formatted-message' instead of '&amp;message' where appropriate.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* gnu.scm (%try-use-modules): Use 'formatted-message' instead of
'&amp;message'.
* gnu/machine/digital-ocean.scm (maybe-raise-unsupported-configuration-error):
Likewise.
* gnu/machine/ssh.scm (machine-check-file-system-availability): Likewise.
(machine-check-building-for-appropriate-system): Likewise.
(deploy-managed-host): Likewise.
(maybe-raise-unsupported-configuration-error): Likewise.
* gnu/packages.scm (search-patch): Likewise.
* gnu/services.scm (%service-with-default-value): Likewise.
(files-&gt;etc-directory): Likewise.
(fold-services): Likewise.
* gnu/system.scm (locale-name-&gt;definition*): Likewise.
* gnu/system/mapped-devices.scm (check-device-initrd-modules): Likewise.
(check-luks-device): Likewise.
* guix/channels.scm (latest-channel-instance): Likewise.
* guix/cve.scm (json-&gt;cve-items): Likewise.
* guix/git-authenticate.scm (commit-signing-key): Likewise.
(commit-authorized-keys): Likewise.
(authenticate-commit): Likewise.
(verify-introductory-commit): Likewise.
* guix/remote.scm (remote-pipe-for-gexp): Likewise.
* guix/scripts/graph.scm (assert-package): Likewise.
* guix/scripts/offload.scm (private-key-from-file*): Likewise.
* guix/ssh.scm (authenticate-server*): Likewise.
(open-ssh-session): Likewise.
(remote-inferior): Likewise.
* guix/ui.scm (matching-generations): Likewise.
* guix/upstream.scm (package-update): Likewise.
* tests/channels.scm ("latest-channel-instances, missing introduction for 'guix'"):
Catch 'formatted-message?'.
("authenticate-channel, wrong first commit signer"): Likewise.
* tests/lint.scm ("patches: not found"): Adjust message string.
* tests/packages.scm ("patch not found yields a run-time error"): Catch
'formatted-message?'.
* guix/lint.scm (check-patch-file-names): Handle 'formatted-message?'.
(check-derivation): Ditto.


</td></tr>
<tr class='logheader'><td><span title='2020-07-25 19:11:36 +0200'>2020-07-25</span></td><td class='logsubject'><a href='/guix/commit/gnu.scm?id=f9a8dd053c4e0fd1fc4b64291bb90de36520b3bc'>utils: Move '&amp;fix-hint' to (guix diagnostics).</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* guix/utils.scm (&amp;fix-hint): Move to...
* guix/diagnostics.scm (&amp;fix-hint): ... here.
* gnu.scm: Adjust imports accordingly.
* gnu/system/mapped-devices.scm: Likewise.
* guix/channels.scm: Likewise.
* guix/profiles.scm: Likewise.
* guix/scripts/system/reconfigure.scm: Likewise.
* guix/ssh.scm: Likewise.


</td></tr>
<tr class='logheader'><td><span title='2020-07-25 19:11:36 +0200'>2020-07-25</span></td><td class='logsubject'><a href='/guix/commit/gnu.scm?id=a5e2fc73760a2ae023f2e56bdbf8025971f90e64'>utils: Move &lt;location&gt; and '&amp;error-location' to (guix diagnostics).</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* guix/utils.scm (&lt;location&gt;, source-properties-&gt;location)
(location-&gt;source-properties, &amp;error-location): Move to...
* guix/diagnostics.scm: ... here.
* gnu.scm: Adjust imports accordingly.
* gnu/machine.scm: Likewise.
* gnu/system.scm: Likewise.
* gnu/tests.scm: Likewise.
* guix/inferior.scm: Likewise.
* tests/channels.scm: Likewise.
* tests/packages.scm: Likewise.


</td></tr>