fix translation of wx priority values to the standard Unix ones in SetPriority()

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@48537 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -172,6 +172,7 @@ wxGTK:
 - Replaced g_free with g_border_free to fix crash with newer GTK+.
 - Fixed crash in settings when using tooltips->tip_window with GTK+ 2.11.6.
 - Fix WX_GL_STEREO attribute handling (Tristan Mehamli)
+- Fix wxThread::SetPriority() when the thread is running (Christos Gourdoupis)
 
 wxMac:
 

src/unix/threadpsx.cpp

@@ -1248,7 +1248,7 @@ void wxThread::SetPriority(unsigned int prio)
 
             // map wx priorites WXTHREAD_MIN_PRIORITY..WXTHREAD_MAX_PRIORITY
             // to Unix priorities 20..-20
-            if ( setpriority(PRIO_PROCESS, 0, -(2*prio)/5 + 20) == -1 )
+            if ( setpriority(PRIO_PROCESS, 0, -(2*(int)prio)/5 + 20) == -1 )
             {
                 wxLogError(_("Failed to set thread priority %d."), prio);
             }