diff --git a/src/exchange/taler-exchange-httpd.c b/src/exchange/taler-exchange-httpd.c
index ffd61873b..b948c315c 100644
--- a/src/exchange/taler-exchange-httpd.c
+++ b/src/exchange/taler-exchange-httpd.c
@@ -130,7 +130,7 @@ static int connection_close;
 /**
  * -I command-line flag given?
  */
-int TEH_check_invariants;
+int TEH_check_invariants_flag;
 
 /**
  * True if we should commit suicide once all active
@@ -1911,7 +1911,7 @@ main (int argc,
     GNUNET_GETOPT_option_flag ('I',
                                "check-invariants",
                                "enable expensive invariant checks",
-                               &TEH_check_invariants),
+                               &TEH_check_invariants_flag),
     GNUNET_GETOPT_option_flag ('r',
                                "allow-reuse-address",
                                "allow multiple HTTPDs to listen to the same port",
diff --git a/src/exchange/taler-exchange-httpd.h b/src/exchange/taler-exchange-httpd.h
index 9a7395011..07f6b0231 100644
--- a/src/exchange/taler-exchange-httpd.h
+++ b/src/exchange/taler-exchange-httpd.h
@@ -147,7 +147,7 @@ extern char *TEH_exchange_directory;
 /**
  * -I command-line flag given?
  */
-extern int TEH_check_invariants;
+extern int TEH_check_invariants_flag;
 
 /**
  * Are clients allowed to request /keys for times other than the
diff --git a/src/exchange/taler-exchange-httpd_keys.c b/src/exchange/taler-exchange-httpd_keys.c
index 1029d2008..86366eaf6 100644
--- a/src/exchange/taler-exchange-httpd_keys.c
+++ b/src/exchange/taler-exchange-httpd_keys.c
@@ -549,7 +549,7 @@ TEH_check_invariants ()
 {
   struct TEH_KeyStateHandle *ksh;
 
-  if (0 == TEH_check_invariants)
+  if (0 == TEH_check_invariants_flag)
     return;
   ksh = TEH_keys_get_state ();
   if (NULL == ksh)