Fix warning (XERCESC-1872)

git-svn-id: https://svn.apache.org/repos/asf/xerces/c/branches/xerces-3.0@789674 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/src/xercesc/util/Transcoders/IconvGNU/IconvGNUTransService.cpp b/src/xercesc/util/Transcoders/IconvGNU/IconvGNUTransService.cpp
index fb75693..ae868ec 100644
--- a/src/xercesc/util/Transcoders/IconvGNU/IconvGNUTransService.cpp
+++ b/src/xercesc/util/Transcoders/IconvGNU/IconvGNUTransService.cpp
@@ -392,7 +392,7 @@
     // Using an empty string instead of NULL, will modify the libc
     // behavior.
     //
-    char* fLocalCP = setlocale (LC_CTYPE, NULL);
+    const char* fLocalCP = setlocale (LC_CTYPE, NULL);
     if (fLocalCP == NULL || *fLocalCP == 0 ||
         strcmp (fLocalCP, "C") == 0 ||
         strcmp (fLocalCP, "POSIX") == 0) {