diff --git a/.dir-locals.el b/.dir-locals.el
index 957ee03..6589692 100644
--- a/.dir-locals.el
+++ b/.dir-locals.el
@@ -1,3 +1,3 @@
 ((nil . ((compile-command . (concat "make -C "
                                        (vc-root-dir)
-                                       " -k -j2 testing")))))
+                                       " -k -j4 testing")))))
diff --git a/Makefile b/Makefile
index 54d7162..4ccdd46 100644
--- a/Makefile
+++ b/Makefile
@@ -97,12 +97,14 @@ CFLAGS    += -ginline-points                                # inlined funcs debu
 #CFLAGS += -mno-tbm
 
 # release
-CFLAGS    += -Ofast
+CFLAGS    += -O3
 
 CFLAGS    += -march=native
 CFLAGS    += -flto
+CFLAGS    += -funroll-loops
 CFLAGS    += -Wall
 CFLAGS    += -Wextra
+CFLAGS    += -Wshadow
 CFLAGS    += -Wmissing-declarations
 
 CFLAGS    := $(strip $(CFLAGS))
diff --git a/test/common-test.h b/test/common-test.h
index abe8560..ca63679 100644
--- a/test/common-test.h
+++ b/test/common-test.h
@@ -412,22 +412,22 @@ struct fentest {
     { __LINE__, 0, NULL, NULL }
 };
 
-static int cur = -1;
+static int fentest_cur = -1;
 
 static char *next_fen(uint module)
 {
-    cur++;
-    while (fentest[cur].fen && !(fentest[cur].modules & module))
-        cur++;
-    return fentest[cur].fen;
+    fentest_cur++;
+    while (fentest[fentest_cur].fen && !(fentest[fentest_cur].modules & module))
+        fentest_cur++;
+    return fentest[fentest_cur].fen;
 }
 
 static __unused char* cur_comment()
 {
-    return fentest[cur].comment;
+    return fentest[fentest_cur].comment;
 }
 
 static __unused int cur_line()
 {
-    return fentest[cur].line;
+    return fentest[fentest_cur].line;
 }