diff --git a/README.developer b/README.developer
index 177717f09..41576a385 100644
--- a/README.developer
+++ b/README.developer
@@ -159,7 +159,7 @@ file.  This document introduces hacking the code of Hamlib.
 
   git clone git://git.code.sf.net/p/hamlib/code hamlib
 
-The clone has to only be done the first time.
+The clone only has to be done the first time.
 
 After the initial clone, whenever you want to update your local
 repository, issue the following command in the root directory of Hamlib:
@@ -277,6 +277,9 @@ distributions may differ).
 * libtool       2.2.6b+                     # libtool --version
 * Git for connection to git.code.sf.net/p/hamlib/code
 
+As of Hamlib 4.7, POSIX thread support (pthreads) is required to compile or
+run Hamlib.
+
 N.B. Hamlib requires libtool >= 2.2.6b in compliance with CVE-2009-3736.
 
 Optional, but highly recommended:
@@ -518,6 +521,7 @@ So far, Hamlib has been tested successfully under the following systems:
     * Debian sid mipsel
     * Raspbian armhf (Raspberry Pi Debian derivative)
     * RedHat i386
+    * openSUSE (Leap & Tumbleweed)
     * Linux ppc
     * Slackware i386
     * FreeBSD & NetBSD
diff --git a/configure.ac b/configure.ac
index 81e045539..150954246 100644
--- a/configure.ac
+++ b/configure.ac
@@ -172,7 +172,7 @@ dnl If pthread support is found, this macro defines HAVE_PTHREAD and
 dnl AC_SUBST's PTHREAD_LIBS, PTHREAD_CFLAGS, and PTHREAD_CC making those
 dnl variables available in Makefiles.
 # macros/ax_pthread.m4
-AX_PTHREAD
+AX_PTHREAD([], [AC_MSG_ERROR([POSIX threads not found])])
 
 AC_SYS_POSIX_TERMIOS()