maint: Use logical rather than bitwise operators on bools

This is because bitwise operators are:
- confusing and inconsistent in a boolean context
- non short circuiting
- brittle in C89 where bool can be an int (so > 1)

1 files changed, 1 insertions, 1 deletions

diff --git a/src/du.c b/src/du.c
index de0cdbdd5..9831a1788 100644
--- a/src/du.c
+++ b/src/du.c
@@ -843,7 +843,7 @@ main (int argc, char **argv)
   if (!ok)
     usage (EXIT_FAILURE);
 
-  if (opt_all & opt_summarize_only)
+  if (opt_all && opt_summarize_only)
     {
       error (0, 0, _("cannot both summarize and show all entries"));
       usage (EXIT_FAILURE);