X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/2a824fae30d1cea0f1e85eee3ce42d5c120299d6..cd735a8c6caab8f705fe551cc0316d0292eef11d:/data/bison.m4

diff --git a/data/bison.m4 b/data/bison.m4
index 9a66d884..178134a4 100644
--- a/data/bison.m4
+++ b/data/bison.m4
@@ -576,3 +576,11 @@ m4_define_default([b4_parse_param], [])
 # The initial column and line.
 m4_define_default([b4_location_initial_column], [1])
 m4_define_default([b4_location_initial_line],   [1])
+
+# Sanity checks.
+b4_percent_define_ifdef([api.prefix],
+[m4_ifdef([b4_prefix],
+[b4_complain_at(b4_percent_define_get_loc([api.prefix]),
+                [['%s' and '%s' cannot be used together]],
+                [%name-prefix],
+                [%define api.prefix])])])