Bugfix in setenv: default argument handling.

* sysif.c (setenv_wrap): We must use default_arg_strict,
not default_arg, because default_arg treats a nil value
as missing. We do not want to replace an explicit nil
with the default t.

1 files changed, 1 insertions, 1 deletions

diff --git a/sysif.c b/sysif.c
index d0a06ca0..1ad5db35 100644
--- a/sysif.c
+++ b/sysif.c
@@ -704,7 +704,7 @@ static val setenv_wrap(val name, val value, val overwrite)
 {
   char *nameu8 = utf8_dup_to(c_str(name));
   char *valu8 = value ? utf8_dup_to(c_str(value)) : 0;
-  int ovw = default_arg(overwrite, t) != nil;
+  int ovw = default_arg_strict(overwrite, t) != nil;
   if (valu8)
     setenv(nameu8, valu8, ovw);
   else if (ovw)