diff --git a/tools/unicode/c/genbidi/store.c b/tools/unicode/c/genbidi/store.c
index f22534aa534..23901ded92d 100644
--- a/tools/unicode/c/genbidi/store.c
+++ b/tools/unicode/c/genbidi/store.c
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 2004-2010, International Business Machines
+*   Copyright (C) 2004-2011, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -384,8 +384,11 @@ generateData(const char *dataDir, UBool csource) {
 
     if(csource) {
         /* write .c file for hardcoded data */
-        FILE *f=usrc_create(dataDir, "ubidi_props_data.c");
+        FILE *f=usrc_create(dataDir, "ubidi_props_data.h");
         if(f!=NULL) {
+            fputs("#ifndef INCLUDED_FROM_UBIDI_PROPS_C\n"
+                  "#   error This file must be #included from ubidi_props.c only.\n"
+                  "#endif\n\n", f);
             usrc_writeArray(f,
                 "static const UVersionInfo ubidi_props_dataVersion={",
                 dataInfo.dataVersion, 8, 4,
diff --git a/tools/unicode/c/gencase/store.c b/tools/unicode/c/gencase/store.c
index 25390424cf4..a6fe0946c1e 100644
--- a/tools/unicode/c/gencase/store.c
+++ b/tools/unicode/c/gencase/store.c
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 2004-2010, International Business Machines
+*   Copyright (C) 2004-2011, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -1120,8 +1120,11 @@ generateData(const char *dataDir, UBool csource) {
 
     if(csource) {
         /* write .c file for hardcoded data */
-        FILE *f=usrc_create(dataDir, "ucase_props_data.c");
+        FILE *f=usrc_create(dataDir, "ucase_props_data.h");
         if(f!=NULL) {
+            fputs("#ifndef INCLUDED_FROM_UCASE_CPP\n"
+                  "#   error This file must be #included from ucase.cpp only.\n"
+                  "#endif\n\n", f);
             usrc_writeArray(f,
                 "static const UVersionInfo ucase_props_dataVersion={",
                 dataInfo.dataVersion, 8, 4,
diff --git a/tools/unicode/c/gennames/gennames.c b/tools/unicode/c/gennames/gennames.c
index d5e5bfd7025..8181260126d 100644
--- a/tools/unicode/c/gennames/gennames.c
+++ b/tools/unicode/c/gennames/gennames.c
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 1999-2010, International Business Machines
+*   Copyright (C) 1999-2011, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -735,7 +735,7 @@ parseName(char *name, int16_t length) {
     }
 }
 
-static UBool U_INLINE
+static UBool
 isWordChar(char c) {
     return ('A'<=c && c<='I') || /* EBCDIC-safe check for letters */
            ('J'<=c && c<='R') ||
diff --git a/tools/unicode/c/genprops/store.c b/tools/unicode/c/genprops/store.c
index f25ccacb4fd..9f9ae290b7e 100644
--- a/tools/unicode/c/genprops/store.c
+++ b/tools/unicode/c/genprops/store.c
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 1999-2010, International Business Machines
+*   Copyright (C) 1999-2011, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -426,8 +426,11 @@ generateData(const char *dataDir, UBool csource) {
 
     if(csource) {
         /* write .c file for hardcoded data */
-        FILE *f=usrc_create(dataDir, "uchar_props_data.c");
+        FILE *f=usrc_create(dataDir, "uchar_props_data.h");
         if(f!=NULL) {
+            fputs("#ifndef INCLUDED_FROM_UCHAR_C\n"
+                  "#   error This file must be #included from uchar.c only.\n"
+                  "#endif\n\n", f);
             /* unused
             usrc_writeArray(f,
                 "static const UVersionInfo formatVersion={",