test PCRE in FreeBSD, Linux, and NetBSD
diff --git a/auto/os/features b/auto/os/features
index 670de98..1e54f9d 100644
--- a/auto/os/features
+++ b/auto/os/features
@@ -30,6 +30,7 @@
 ngx_feature_name=
 ngx_feature_run=no
 ngx_feature_incs="#include <poll.h>"
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="int  n, dp; struct pollfd  pl;
                   dp = 0;
@@ -48,6 +49,7 @@
 ngx_feature_name="NGX_HAVE_DEVPOLL"
 ngx_feature_run=no
 ngx_feature_incs="#include <sys/devpoll.h>"
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="int  n, dp; struct dvpoll  dvp;
                   dp = 0;
@@ -69,6 +71,7 @@
     ngx_feature_name="NGX_HAVE_KQUEUE"
     ngx_feature_run=no
     ngx_feature_incs="#include <sys/event.h>"
+    ngx_feature_path=
     ngx_feature_libs=
     ngx_feature_test="int kq; kq = kqueue()"
     . auto/feature
@@ -84,6 +87,7 @@
         ngx_feature_name="NGX_HAVE_LOWAT_EVENT"
         ngx_feature_run=no
         ngx_feature_incs="#include <sys/event.h>"
+        ngx_feature_path=
         ngx_feature_libs=
         ngx_feature_test="struct kevent  kev;
                           kev.fflags = NOTE_LOWAT;"
@@ -95,6 +99,7 @@
         ngx_feature_run=yes
         ngx_feature_incs="#include <sys/event.h>
 #include <sys/time.h>"
+        ngx_feature_path=
         ngx_feature_libs=
         ngx_feature_test="int      kq;
                   struct kevent    kev;
@@ -126,6 +131,7 @@
             ngx_feature_run=bug
             ngx_feature_incs="#include <sys/event.h>
 #include <sys/time.h>"
+            ngx_feature_path=
             ngx_feature_libs=
             ngx_feature_test="int  kq;
                   struct kevent    kev;
@@ -174,6 +180,7 @@
 ngx_feature_name=
 ngx_feature_run=no
 ngx_feature_incs=
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="crypt(\"test\", \"salt\");"
 . auto/feature
@@ -182,6 +189,10 @@
 if [ $ngx_found = no ]; then
 
     ngx_feature="crypt() in libcrypt"
+    ngx_feature_name=
+    ngx_feature_run=no
+    ngx_feature_incs=
+    ngx_feature_path=
     ngx_feature_libs=-lcrypt
     . auto/feature
 
diff --git a/auto/os/linux b/auto/os/linux
index 4136486..abf61f1 100644
--- a/auto/os/linux
+++ b/auto/os/linux
@@ -40,6 +40,7 @@
 ngx_feature_name="NGX_HAVE_EPOLL"
 ngx_feature_run=yes
 ngx_feature_incs="#include <sys/epoll.h>"
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="int efd = 0, fd = 1, n;
                   struct epoll_event ee;
@@ -65,6 +66,7 @@
 ngx_feature_run=yes
 ngx_feature_incs="#include <sys/sendfile.h>
 #include <errno.h>"
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="int s = 0, fd = 1;
                   ssize_t n; off_t off = 0;
@@ -85,6 +87,7 @@
 ngx_feature_run=yes
 ngx_feature_incs="#include <sys/sendfile.h>
 #include <errno.h>"
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="int s = 0, fd = 1;
                   ssize_t n; off_t off = 0;
@@ -101,6 +104,7 @@
 ngx_feature_name="NGX_HAVE_PR_SET_DUMPABLE"
 ngx_feature_run=yes
 ngx_feature_incs="#include <sys/prctl.h>"
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="if (prctl(PR_SET_DUMPABLE, 1, 0, 0, 0) == -1) return 1"
 . auto/feature
@@ -112,6 +116,7 @@
 ngx_feature_name="NGX_HAVE_SCHED_SETAFFINITY"
 ngx_feature_run=no
 ngx_feature_incs="#include <sched.h>"
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="long mask = 0;
                   sched_setaffinity(0, 32, (cpu_set_t *) &mask)"
diff --git a/auto/os/solaris b/auto/os/solaris
index 757013d..5a46ee6 100644
--- a/auto/os/solaris
+++ b/auto/os/solaris
@@ -28,6 +28,7 @@
 ngx_feature_name="NGX_HAVE_SENDFILE"
 ngx_feature_run=no
 ngx_feature_incs="#include <sys/sendfile.h>"
+ngx_feature_path=
 ngx_feature_libs="-lsendfile"
 ngx_feature_test="int fd = 1; sendfilevec_t vec[1];
                   size_t sent; ssize_t n;
@@ -45,6 +46,7 @@
 ngx_feature_name="NGX_HAVE_EVENTPORT"
 ngx_feature_run=no
 ngx_feature_incs="#include <port.h>"
+ngx_feature_path=
 ngx_feature_libs=
 ngx_feature_test="int n = port_create()"
 . auto/feature