diff --git a/ctemplate/src/ctemplate/template_string.h b/ctemplate/src/ctemplate/template_string.h
index d2a4e62..18fe938 100644
--- a/ctemplate/src/ctemplate/template_string.h
+++ b/ctemplate/src/ctemplate/template_string.h
@@ -337,7 +337,7 @@ class  StaticTemplateStringInitializer {
 
 // Don't use this.  This is used only in auto-generated .varnames.h files.
 #define STS_INIT_WITH_HASH(name, str, hash)                                   \
-  { { str, sizeof(""str"")-1, hash } };                                       \
+  { { str, sizeof("" str "")-1, hash } };                                       \
   namespace ctemplate_sts_init {                                              \
   static const ::ctemplate::StaticTemplateStringInitializer name##_init(&name); \
   }
diff --git a/ctemplate/src/ctemplate/template_string.h.in b/ctemplate/src/ctemplate/template_string.h.in
index 6fa999d..701c36c 100644
--- a/ctemplate/src/ctemplate/template_string.h.in
+++ b/ctemplate/src/ctemplate/template_string.h.in
@@ -337,7 +337,7 @@ class @ac_windows_dllexport@ StaticTemplateStringInitializer {
 
 // Don't use this.  This is used only in auto-generated .varnames.h files.
 #define STS_INIT_WITH_HASH(name, str, hash)                                   \
-  { { str, sizeof(""str"")-1, hash } };                                       \
+  { { str, sizeof("" str "")-1, hash } };                                       \
   namespace ctemplate_sts_init {                                              \
   static const @ac_google_namespace@::StaticTemplateStringInitializer name##_init(&name); \
   }