Move operating system detection from qglobal.h to a separate header

qsystemdetection.h is included from qglobal.h, and does all Q_OS_*
detection

A side-effect of this change is that QT_BEGIN_HEADER and QT_END_HEADER
started being defined on Mac OS X, which ends up breaking the build
in some cases. Since QT_BEGIN_HEADER and QT_END_HEADER have been
defined to nothing in the past, even on Mac OS X, change these 2
to be unconditionally defined to nothing.

Change-Id: Ibc8a0aa2207664741c25627d7621e006c2ce80d3
Reviewed-by: Thiago Macieira <[email protected]>

Author: Bradley T. Hughes

src/corelib/global/global.pri

@@ -2,6 +2,7 @@
 
 HEADERS +=  \
 	global/qglobal.h \
+        global/qsystemdetection.h \
 	global/qnamespace.h \
         global/qendian.h \
         global/qnumeric_p.h \

src/corelib/global/qglobal.h

@@ -62,6 +62,8 @@
 #include <QtCore/qconfig.h>
 #endif
 
+#include <QtCore/qsystemdetection.h>
+
 #ifdef __cplusplus
 
 #ifndef QT_NO_STL
@@ -140,181 +142,13 @@ namespace QT_NAMESPACE {}
 
 #endif /* __cplusplus */
 
-#if defined(Q_OS_MAC) && !defined(Q_CC_INTEL)
-#define QT_BEGIN_HEADER extern "C++" {
-#define QT_END_HEADER }
-#else
 #define QT_BEGIN_HEADER
 #define QT_END_HEADER
-#endif
-
-/*
-   The operating system, must be one of: (Q_OS_x)
-
-     DARWIN   - Darwin OS (synonym for Q_OS_MAC)
-     MSDOS    - MS-DOS and Windows
-     OS2      - OS/2
-     OS2EMX   - XFree86 on OS/2 (not PM)
-     WIN32    - Win32 (Windows 2000/XP/Vista/7 and Windows Server 2003/2008)
-     WINCE    - WinCE (Windows CE 5.0)
-     CYGWIN   - Cygwin
-     SOLARIS  - Sun Solaris
-     HPUX     - HP-UX
-     ULTRIX   - DEC Ultrix
-     LINUX    - Linux
-     FREEBSD  - FreeBSD
-     NETBSD   - NetBSD
-     OPENBSD  - OpenBSD
-     BSDI     - BSD/OS
-     IRIX     - SGI Irix
-     OSF      - HP Tru64 UNIX
-     SCO      - SCO OpenServer 5
-     UNIXWARE - UnixWare 7, Open UNIX 8
-     AIX      - AIX
-     HURD     - GNU Hurd
-     DGUX     - DG/UX
-     RELIANT  - Reliant UNIX
-     DYNIX    - DYNIX/ptx
-     QNX      - QNX
-     QNX6     - QNX RTP 6.1
-     LYNX     - LynxOS
-     BSD4     - Any BSD 4.4 system
-     UNIX     - Any UNIX BSD/SYSV system
-*/
-
-#if defined(__APPLE__) && (defined(__GNUC__) || defined(__xlC__) || defined(__xlc__))
-#  define Q_OS_DARWIN
-#  define Q_OS_BSD4
-#  ifdef __LP64__
-#    define Q_OS_DARWIN64
-#  else
-#    define Q_OS_DARWIN32
-#  endif
-#elif defined(__CYGWIN__)
-#  define Q_OS_CYGWIN
-#elif !defined(SAG_COM) && (defined(WIN64) || defined(_WIN64) || defined(__WIN64__))
-#  define Q_OS_WIN32
-#  define Q_OS_WIN64
-#elif !defined(SAG_COM) && (defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__NT__))
-#  if defined(WINCE) || defined(_WIN32_WCE)
-#    define Q_OS_WINCE
-#  else
-#    define Q_OS_WIN32
-#  endif
-#elif defined(__sun) || defined(sun)
-#  define Q_OS_SOLARIS
-#elif defined(hpux) || defined(__hpux)
-#  define Q_OS_HPUX
-#elif defined(__ultrix) || defined(ultrix)
-#  define Q_OS_ULTRIX
-#elif defined(sinix)
-#  define Q_OS_RELIANT
-#elif defined(__native_client__)
-#  define Q_OS_NACL
-#elif defined(__linux__) || defined(__linux)
-#  define Q_OS_LINUX
-#elif defined(__FreeBSD__) || defined(__DragonFly__)
-#  define Q_OS_FREEBSD
-#  define Q_OS_BSD4
-#elif defined(__NetBSD__)
-#  define Q_OS_NETBSD
-#  define Q_OS_BSD4
-#elif defined(__OpenBSD__)
-#  define Q_OS_OPENBSD
-#  define Q_OS_BSD4
-#elif defined(__bsdi__)
-#  define Q_OS_BSDI
-#  define Q_OS_BSD4
-#elif defined(__sgi)
-#  define Q_OS_IRIX
-#elif defined(__osf__)
-#  define Q_OS_OSF
-#elif defined(_AIX)
-#  define Q_OS_AIX
-#elif defined(__Lynx__)
-#  define Q_OS_LYNX
-#elif defined(__GNU__)
-#  define Q_OS_HURD
-#elif defined(__DGUX__)
-#  define Q_OS_DGUX
-#elif defined(__QNXNTO__)
-#  define Q_OS_QNX
-#elif defined(_SEQUENT_)
-#  define Q_OS_DYNIX
-#elif defined(_SCO_DS) /* SCO OpenServer 5 + GCC */
-#  define Q_OS_SCO
-#elif defined(__USLC__) /* all SCO platforms + UDK or OUDK */
-#  define Q_OS_UNIXWARE
-#elif defined(__svr4__) && defined(i386) /* Open UNIX 8 + GCC */
-#  define Q_OS_UNIXWARE
-#elif defined(__INTEGRITY)
-#  define Q_OS_INTEGRITY
-#elif defined(VXWORKS) /* there is no "real" VxWorks define - this has to be set in the mkspec! */
-#  define Q_OS_VXWORKS
-#elif defined(__MAKEDEPEND__)
-#else
-#  error "Qt has not been ported to this OS - see http://www.qt-project.org/"
-#endif
-
-#if defined(Q_OS_WIN32) || defined(Q_OS_WIN64) || defined(Q_OS_WINCE)
-#  define Q_OS_WIN
-#endif
-
-#if defined(Q_OS_DARWIN)
-#  define Q_OS_MAC
-#  define Q_OS_MACX /* Q_OS_MACX is only for compatibility.*/
-#  if defined(Q_OS_DARWIN64)
-#     define Q_OS_MAC64
-#  elif defined(Q_OS_DARWIN32)
-#     define Q_OS_MAC32
-#  endif
-#endif
-
-#if defined(Q_OS_WIN)
-#  undef Q_OS_UNIX
-#elif !defined(Q_OS_UNIX)
-#  define Q_OS_UNIX
-#endif
 
 #if defined(Q_OS_DARWIN) && !defined(QT_LARGEFILE_SUPPORT)
 #  define QT_LARGEFILE_SUPPORT 64
 #endif
 
-#ifdef Q_OS_DARWIN
-#  ifdef MAC_OS_X_VERSION_MIN_REQUIRED
-#    undef MAC_OS_X_VERSION_MIN_REQUIRED
-#  endif
-#  define MAC_OS_X_VERSION_MIN_REQUIRED MAC_OS_X_VERSION_10_4
-#  include <AvailabilityMacros.h>
-#  if !defined(MAC_OS_X_VERSION_10_3)
-#     define MAC_OS_X_VERSION_10_3 MAC_OS_X_VERSION_10_2 + 1
-#  endif
-#  if !defined(MAC_OS_X_VERSION_10_4)
-#       define MAC_OS_X_VERSION_10_4 MAC_OS_X_VERSION_10_3 + 1
-#  endif
-#  if !defined(MAC_OS_X_VERSION_10_5)
-#       define MAC_OS_X_VERSION_10_5 MAC_OS_X_VERSION_10_4 + 1
-#  endif
-#  if !defined(MAC_OS_X_VERSION_10_6)
-#       define MAC_OS_X_VERSION_10_6 MAC_OS_X_VERSION_10_5 + 1
-#  endif
-#  if !defined(MAC_OS_X_VERSION_10_7)
-#       define MAC_OS_X_VERSION_10_7 MAC_OS_X_VERSION_10_6 + 1
-#  endif
-#  if (MAC_OS_X_VERSION_MAX_ALLOWED > MAC_OS_X_VERSION_10_7)
-#    warning "This version of Mac OS X is unsupported"
-#  endif
-#endif
-
-#ifdef __LSB_VERSION__
-#  if __LSB_VERSION__ < 40
-#    error "This version of the Linux Standard Base is unsupported"
-#  endif
-#ifndef QT_LINUXBASE
-#  define QT_LINUXBASE
-#endif
-#endif
-
 /*
    The compiler, must be one of: (Q_CC_x)