(child_setup) [MSDOS]: malloc pwd_var instead of

using alloca; free it after run_msdos_command returns

1 files changed, 8 insertions, 0 deletions

diff --git a/src/callproc.c b/src/callproc.c
index 16ae6ada73c..a79816b2f38 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -1072,7 +1072,14 @@ child_setup (in, out, err, new_argv, set_pgrp, current_dir)
     register int i;
 
     i = STRING_BYTES (XSTRING (current_dir));
+#ifdef MSDOS
+    /* MSDOS must have all environment variables malloc'ed, because
+       low-level libc functions that launch subsidiary processes rely
+       on that.  */
+    pwd_var = (char *) xmalloc (i + 6);
+#else
     pwd_var = (char *) alloca (i + 6);
+#endif
     temp = pwd_var + 4;
     bcopy ("PWD=", pwd_var, 4);
     bcopy (XSTRING (current_dir)->data, temp, i);
@@ -1212,6 +1219,7 @@ child_setup (in, out, err, new_argv, set_pgrp, current_dir)
 
 #ifdef MSDOS
   pid = run_msdos_command (new_argv, pwd_var + 4, in, out, err, env);
+  free (pwd_var);
   if (pid == -1)
     /* An error occurred while trying to run the subprocess.  */
     report_file_error ("Spawning child process", Qnil);