build_env(): respect the MSYS environment variable

dscho · dscho · commit 24df6e4c3fd3 · 2025-06-05T13:52:03.000+02:00
With this commit, you can call

	MSYS=noemptyenvvalues my-command

and it does what is expected: to pass no empty-valued environment
variables to `my-command`.

Signed-off-by: Johannes Schindelin &lt;johannes.schindelin@gmx.de&gt;
diff --git a/winsup/cygwin/environ.cc b/winsup/cygwin/environ.cc
@@ -1204,7 +1204,11 @@ build_env (const char * const *envp, PWCHAR &envblock, int &envc,
     {
       bool calc_tl = !no_envblock;
 #ifdef __MSYS__
-      if (!keep_posix)
+      if (ascii_strncasematch(*srcp, "MSYS=", 5))
+        {
+          parse_options (*srcp + 5);
+	}
+      else if (!keep_posix)
         {
           /* Don't pass timezone environment to non-msys applications */
           if (ascii_strncasematch(*srcp, "TZ=", 3))

Original file line number	Diff line number	Diff line change
`@@ -1204,7 +1204,11 @@ build_env (const char * const *envp, PWCHAR &envblock, int &envc,`
`1204`	`1204`	`{`
`1205`	`1205`	`bool calc_tl = !no_envblock;`
`1206`	`1206`	`#ifdef __MSYS__`
`1207`		`- if (!keep_posix)`
	`1207`	`+ if (ascii_strncasematch(*srcp, "MSYS=", 5))`
	`1208`	`+ {`
	`1209`	`+ parse_options (*srcp + 5);`
	`1210`	`+ }`
	`1211`	`+ else if (!keep_posix)`
`1208`	`1212`	`{`
`1209`	`1213`	`/* Don't pass timezone environment to non-msys applications */`
`1210`	`1214`	`if (ascii_strncasematch(*srcp, "TZ=", 3))`