The comment form mangled my diff.
---
diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
index a922819..141494c 100644
--- a/doc/src/sgml/installation.sgml
+++ b/doc/src/sgml/installation.sgml
@@ -289,7 +289,7 @@ su - postgres
<primary>yacc</primary>
</indexterm>
- GNU <application>Flex</application> and <application>Bison</application>
+ <application>Flex</application> and <application>Bison</application>
are needed to build from a Git checkout, or if you changed the actual
scanner and parser definition files. If you need them, be sure
to get <application>Flex</application> 2.5.31 or later and
