diff --git a/Cantera/src/equil/vcs_util.cpp b/Cantera/src/equil/vcs_util.cpp
index 21541b857..ae34e3a12 100644
--- a/Cantera/src/equil/vcs_util.cpp
+++ b/Cantera/src/equil/vcs_util.cpp
@@ -415,7 +415,7 @@ namespace VCSnonideal {
 
 
   const char *vcs_speciesType_string(int speciesStatus, int length) {
-    char *sss;
+    const char *sss;
     switch (speciesStatus) {
     case VCS_SPECIES_COMPONENT:
       sss = "Component Species";