Link to pthreads on non-apple unix

CMakeLists.txt

@@ -12,7 +12,7 @@ function(set_static_flags)
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -static-libgcc -static-libstdc++")
   endif()
 endfunction(set_static_flags)
-  
+
 include_directories(src contrib/epee/include external "${CMAKE_BINARY_DIR}/version")
 
 if(APPLE)
@@ -21,6 +21,11 @@ endif()
 
 set(STATIC ${MSVC} CACHE BOOL "Link libraries statically")
 
+if (UNIX AND NOT APPLE)
+  # Note that at the time of this writing the -Wstrict-prototypes flag added below will make this fail
+  find_package(Threads REQUIRED)
+endif()
+
 if(MSVC)
   add_definitions("/bigobj /MP /W3 /GS- /D_CRT_SECURE_NO_WARNINGS /wd4996 /wd4345 /D_WIN32_WINNT=0x0600 /DWIN32_LEAN_AND_MEAN /DGTEST_HAS_TR1_TUPLE=0 /FIinline_c.h /D__SSE4_1__")
   # set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /Dinline=__inline")