Submitted for upstream inclusion at: https://github.com/eclipse/mosquitto/pull/360 diff -u -r ../mosquitto-1.4.10/src/CMakeLists.txt ./src/CMakeLists.txt --- ../mosquitto-1.4.10/src/CMakeLists.txt 2016-08-17 13:05:14.000000000 +0200 +++ ./src/CMakeLists.txt 2017-01-24 22:30:42.611308509 +0100 @@ -86,7 +86,11 @@ if (APPLE) set (MOSQ_LIBS ${MOSQ_LIBS} dl m) else (APPLE) - set (MOSQ_LIBS ${MOSQ_LIBS} rt dl m) + set (MOSQ_LIBS ${MOSQ_LIBS} dl m) + find_library(LIBRT rt) + if (LIBRT) + set (MOSQ_LIBS ${MOSQ_LIBS} rt) + endif (LIBRT) endif (APPLE) endif (UNIX) diff -u -r ../mosquitto-1.4.10/lib/CMakeLists.txt ./lib/CMakeLists.txt --- ../mosquitto-1.4.10/lib/CMakeLists.txt 2016-08-17 13:05:14.000000000 +0200 +++ ./lib/CMakeLists.txt 2017-01-15 21:09:21.548573341 +0100 @@ -7,7 +7,12 @@ set (PTHREAD_LIBRARIES C:\\pthreads\\Pre-built.2\\lib\\x86\\pthreadVC2.lib) set (PTHREAD_INCLUDE_DIR C:\\pthreads\\Pre-built.2\\include) else (WIN32) - set (PTHREAD_LIBRARIES pthread) + find_library(LIBPTHREAD pthread) + if (LIBPTHREAD) + set (PTHREAD_LIBRARIES pthread) + else (LIBPTHREAD) + set (PTHREAD_LIBRARIES "") + endif() set (PTHREAD_INCLUDE_DIR "") endif (WIN32) else (${WITH_THREADING} STREQUAL ON) @@ -44,7 +49,10 @@ set (LIBRARIES ${OPENSSL_LIBRARIES} ${PTHREAD_LIBRARIES}) if (UNIX AND NOT APPLE) - set (LIBRARIES ${LIBRARIES} rt) + find_library(LIBRT rt) + if (LIBRT) + set (LIBRARIES ${LIBRARIES} rt) + endif (LIBRT) endif (UNIX AND NOT APPLE) if (WIN32)