diff --git a/src/backend/regex/regcomp.c b/src/backend/regex/regcomp.c
index ed95474b3f..0834ae6e06 100644
--- a/src/backend/regex/regcomp.c
+++ b/src/backend/regex/regcomp.c
@@ -34,8 +34,6 @@
 
 #include "regex/regguts.h"
 
-#include "miscadmin.h"			/* needed by rcancelrequested/rstacktoodeep */
-
 /*
  * forward declarations, up here so forward datatypes etc. are defined early
  */
diff --git a/src/include/regex/regcustom.h b/src/include/regex/regcustom.h
index 04a1893c80..82c9e2fad8 100644
--- a/src/include/regex/regcustom.h
+++ b/src/include/regex/regcustom.h
@@ -29,6 +29,13 @@
  */
 
 /* headers if any */
+
+/*
+ * It's against Postgres coding conventions to include postgres.h in a
+ * header file, but we allow the violation here because the regexp library
+ * files specifically intend this file to supply application-dependent
+ * headers, and are careful to include this file before anything else.
+ */
 #include "postgres.h"
 
 #include <ctype.h>
@@ -47,6 +54,8 @@
 
 #include "mb/pg_wchar.h"
 
+#include "miscadmin.h"			/* needed by rcancelrequested/rstacktoodeep */
+
 
 /* overrides for regguts.h definitions, if any */
 #define FUNCPTR(name, args) (*name) args
diff --git a/src/include/snowball/header.h b/src/include/snowball/header.h
index 9501f77ac1..d8be02ee60 100644
--- a/src/include/snowball/header.h
+++ b/src/include/snowball/header.h
@@ -22,6 +22,11 @@
 #ifndef SNOWBALL_HEADR_H
 #define SNOWBALL_HEADR_H
 
+/*
+ * It's against Postgres coding conventions to include postgres.h in a
+ * header file, but we allow the violation here because the alternative is
+ * to modify the machine-generated .c files provided by the Snowball project.
+ */
 #include "postgres.h"
 
 /* Some platforms define MAXINT and/or MININT, causing conflicts */