【1】不同操作系统的宏
可以参考QtCore/qsystemdetection.h文件：
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For further 15 ** information use the contact form at https://www.qt.io/contact-us. 16 ** 17 ** GNU Lesser General Public License Usage 18 ** Alternatively, this file may be used under the terms of the GNU Lesser 19 ** General Public License version 3 as published by the Free Software 20 ** Foundation and appearing in the file LICENSE.LGPL3 included in the 21 ** packaging of this file. Please review the following information to 22 ** ensure the GNU Lesser General Public License version 3 requirements 23 ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. 24 ** 25 ** GNU General Public License Usage 26 ** Alternatively, this file may be used under the terms of the GNU 27 ** General Public License version 2.0 or (at your option) the GNU General 28 ** Public license version 3 or any later version approved by the KDE Free 29 ** Qt Foundation. The licenses are as published by the Free Software 30 ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 31 ** included in the packaging of this file. Please review the following 32 ** information to ensure the GNU General Public License requirements will 33 ** be met: https://www.gnu.org/licenses/gpl-2.0.html and 34 ** https://www.gnu.org/licenses/gpl-3.0.html. 35 ** 36 ** $QT_END_LICENSE$ 37 ** 38 ****************************************************************************/ 39 40 #ifndef QGLOBAL_H 41 # include <QtCore/qglobal.h> 42 #endif 43 44 #ifndef QSYSTEMDETECTION_H 45 #define QSYSTEMDETECTION_H 46 47 /* 48 The operating system, must be one of: (Q_OS_x) 49 50 DARWIN - Any Darwin system (macOS, iOS, watchOS, tvOS) 51 MACOS - macOS 52 IOS - iOS 53 WATCHOS - watchOS 54 TVOS - tvOS 55 MSDOS - MS-DOS and Windows 56 OS2 - OS/2 57 OS2EMX - XFree86 on OS/2 (not PM) 58 WIN32 - Win32 (Windows 2000/XP/Vista/7 and Windows Server 2003/2008) 59 WINRT - WinRT (Windows 8 Runtime) 60 CYGWIN - Cygwin 61 SOLARIS - Sun Solaris 62 HPUX - HP-UX 63 ULTRIX - DEC Ultrix 64 LINUX - Linux [has variants] 65 FREEBSD - FreeBSD [has variants] 66 NETBSD - NetBSD 67 OPENBSD - OpenBSD 68 BSDI - BSD/OS 69 INTERIX - Interix 70 IRIX - SGI Irix 71 OSF - HP Tru64 UNIX 72 SCO - SCO OpenServer 5 73 UNIXWARE - UnixWare 7, Open UNIX 8 74 AIX - AIX 75 HURD - GNU Hurd 76 DGUX - DG/UX 77 RELIANT - Reliant UNIX 78 DYNIX - DYNIX/ptx 79 QNX - QNX [has variants] 80 QNX6 - QNX RTP 6.1 81 LYNX - LynxOS 82 BSD4 - Any BSD 4.4 system 83 UNIX - Any UNIX BSD/SYSV system 84 ANDROID - Android platform 85 HAIKU - Haiku 86 87 The following operating systems have variants: 88 LINUX - both Q_OS_LINUX and Q_OS_ANDROID are defined when building for Android 89 - only Q_OS_LINUX is defined if building for other Linux systems 90 FREEBSD - Q_OS_FREEBSD is defined only when building for FreeBSD with a BSD userland 91 - Q_OS_FREEBSD_KERNEL is always defined on FreeBSD, even if the userland is from GNU 92 */ 93 94 #if defined(__APPLE__) && (defined(__GNUC__) || defined(__xlC__) || defined(__xlc__)) 95 # include <TargetConditionals.h> 96 # if defined(TARGET_OS_MAC) && TARGET_OS_MAC 97 # define Q_OS_DARWIN 98 # define Q_OS_BSD4 99 # ifdef __LP64__ 100 # define Q_OS_DARWIN64 101 # else 102 # define Q_OS_DARWIN32 103 # endif 104 # if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE 105 # define QT_PLATFORM_UIKIT 106 # if defined(TARGET_OS_WATCH) && TARGET_OS_WATCH 107 # define Q_OS_WATCHOS 108 # elif defined(TARGET_OS_TV) && TARGET_OS_TV 109 # define Q_OS_TVOS 110 # else 111 # // TARGET_OS_IOS is only available in newer SDKs, 112 # // so assume any other iOS-based platform is iOS for now 113 # define Q_OS_IOS 114 # endif 115 # else 116 # // TARGET_OS_OSX is only available in newer SDKs, 117 # // so assume any non iOS-based platform is macOS for now 118 # define Q_OS_MACOS 119 # endif 120 # else 121 # error "Qt has not been ported to this Apple platform - see http://www.qt.io/developers" 122 # endif 123 #elif defined(__ANDROID__) || defined(ANDROID) 124 # define Q_OS_ANDROID 125 # define Q_OS_LINUX 126 #elif defined(__CYGWIN__) 127 # define Q_OS_CYGWIN 128 #elif !defined(SAG_COM) && (!defined(WINAPI_FAMILY) || WINAPI_FAMILY==WINAPI_FAMILY_DESKTOP_APP) && (defined(WIN64) || defined(_WIN64) || defined(__WIN64__)) 129 # define Q_OS_WIN32 130 # define Q_OS_WIN64 131 #elif !defined(SAG_COM) && (defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__NT__)) 132 # if defined(WINAPI_FAMILY) 133 # ifndef WINAPI_FAMILY_PC_APP 134 # define WINAPI_FAMILY_PC_APP WINAPI_FAMILY_APP 135 # endif 136 # if defined(WINAPI_FAMILY_PHONE_APP) && WINAPI_FAMILY==WINAPI_FAMILY_PHONE_APP 137 # define Q_OS_WINRT 138 # elif WINAPI_FAMILY==WINAPI_FAMILY_PC_APP 139 # define Q_OS_WINRT 140 # else 141 # define Q_OS_WIN32 142 # endif 143 # else 144 # define Q_OS_WIN32 145 # endif 146 #elif defined(__sun) || defined(sun) 147 # define Q_OS_SOLARIS 148 #elif defined(hpux) || defined(__hpux) 149 # define Q_OS_HPUX 150 #elif defined(__ultrix) || defined(ultrix) 151 # define Q_OS_ULTRIX 152 #elif defined(sinix) 153 # define Q_OS_RELIANT 154 #elif defined(__native_client__) 155 # define Q_OS_NACL 156 #elif defined(__linux__) || defined(__linux) 157 # define Q_OS_LINUX 158 #elif defined(__FreeBSD__) || defined(__DragonFly__) || defined(__FreeBSD_kernel__) 159 # ifndef __FreeBSD_kernel__ 160 # define Q_OS_FREEBSD 161 # endif 162 # define Q_OS_FREEBSD_KERNEL 163 # define Q_OS_BSD4 164 #elif defined(__NetBSD__) 165 # define Q_OS_NETBSD 166 # define Q_OS_BSD4 167 #elif defined(__OpenBSD__) 168 # define Q_OS_OPENBSD 169 # define Q_OS_BSD4 170 #elif defined(__bsdi__) 171 # define Q_OS_BSDI 172 # define Q_OS_BSD4 173 #elif defined(__INTERIX) 174 # define Q_OS_INTERIX 175 # define Q_OS_BSD4 176 #elif defined(__sgi) 177 # define Q_OS_IRIX 178 #elif defined(__osf__) 179 # define Q_OS_OSF 180 #elif defined(_AIX) 181 # define Q_OS_AIX 182 #elif defined(__Lynx__) 183 # define Q_OS_LYNX 184 #elif defined(__GNU__) 185 # define Q_OS_HURD 186 #elif defined(__DGUX__) 187 # define Q_OS_DGUX 188 #elif defined(__QNXNTO__) 189 # define Q_OS_QNX 190 #elif defined(_SEQUENT_) 191 # define Q_OS_DYNIX 192 #elif defined(_SCO_DS) /* SCO OpenServer 5 + GCC */ 193 # define Q_OS_SCO 194 #elif defined(__USLC__) /* all SCO platforms + UDK or OUDK */ 195 # define Q_OS_UNIXWARE 196 #elif defined(__svr4__) && defined(i386) /* Open UNIX 8 + GCC */ 197 # define Q_OS_UNIXWARE 198 #elif defined(__INTEGRITY) 199 # define Q_OS_INTEGRITY 200 #elif defined(VXWORKS) /* there is no "real" VxWorks define - this has to be set in the mkspec! */ 201 # define Q_OS_VXWORKS 202 #elif defined(__HAIKU__) 203 # define Q_OS_HAIKU 204 #elif defined(__MAKEDEPEND__) 205 #else 206 # error "Qt has not been ported to this OS - see http://www.qt-project.org/" 207 #endif 208 209 #if defined(Q_OS_WIN32) || defined(Q_OS_WIN64) || defined(Q_OS_WINRT) 210 # define Q_OS_WIN 211 #endif 212 213 #if defined(Q_OS_WIN) 214 # undef Q_OS_UNIX 215 #elif !defined(Q_OS_UNIX) 216 # define Q_OS_UNIX 217 #endif 218 219 // Compatibility synonyms 220 #ifdef Q_OS_DARWIN 221 #define Q_OS_MAC 222 #endif 223 #ifdef Q_OS_DARWIN32 224 #define Q_OS_MAC32 225 #endif 226 #ifdef Q_OS_DARWIN64 227 #define Q_OS_MAC64 228 #endif 229 #ifdef Q_OS_MACOS 230 #define Q_OS_MACX 231 #define Q_OS_OSX 232 #endif 233 234 #ifdef Q_OS_DARWIN 235 # include <Availability.h> 236 # include <AvailabilityMacros.h> 237 # 238 # ifdef Q_OS_MACOS 239 # if !defined(__MAC_OS_X_VERSION_MIN_REQUIRED) || __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_6 240 # undef __MAC_OS_X_VERSION_MIN_REQUIRED 241 # define __MAC_OS_X_VERSION_MIN_REQUIRED __MAC_10_6 242 # endif 243 # if !defined(MAC_OS_X_VERSION_MIN_REQUIRED) || MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_6 244 # undef MAC_OS_X_VERSION_MIN_REQUIRED 245 # define MAC_OS_X_VERSION_MIN_REQUIRED MAC_OS_X_VERSION_10_6 246 # endif 247 # endif 248 # 249 # // Numerical checks are preferred to named checks, but to be safe 250 # // we define the missing version names in case Qt uses them. 251 # 252 # if !defined(__MAC_10_7) 253 # define __MAC_10_7 1070 254 # endif 255 # if !defined(__MAC_10_8) 256 # define __MAC_10_8 1080 257 # endif 258 # if !defined(__MAC_10_9) 259 # define __MAC_10_9 1090 260 # endif 261 # if !defined(__MAC_10_10) 262 # define __MAC_10_10 101000 263 # endif 264 # if !defined(__MAC_10_11) 265 # define __MAC_10_11 101100 266 # endif 267 # if !defined(__MAC_10_12) 268 # define __MAC_10_12 101200 269 # endif 270 # if !defined(__MAC_10_13) 271 # define __MAC_10_13 101300 272 # endif 273 # if !defined(MAC_OS_X_VERSION_10_7) 274 # define MAC_OS_X_VERSION_10_7 1070 275 # endif 276 # if !defined(MAC_OS_X_VERSION_10_8) 277 # define MAC_OS_X_VERSION_10_8 1080 278 # endif 279 # if !defined(MAC_OS_X_VERSION_10_9) 280 # define MAC_OS_X_VERSION_10_9 1090 281 # endif 282 # if !defined(MAC_OS_X_VERSION_10_10) 283 # define MAC_OS_X_VERSION_10_10 101000 284 # endif 285 # if !defined(MAC_OS_X_VERSION_10_11) 286 # define MAC_OS_X_VERSION_10_11 101100 287 # endif 288 # if !defined(MAC_OS_X_VERSION_10_12) 289 # define MAC_OS_X_VERSION_10_12 101200 290 # endif 291 # if !defined(MAC_OS_X_VERSION_10_13) 292 # define MAC_OS_X_VERSION_10_13 101300 293 # endif 294 # 295 # if !defined(__IPHONE_4_3) 296 # define __IPHONE_4_3 40300 297 # endif 298 # if !defined(__IPHONE_5_0) 299 # define __IPHONE_5_0 50000 300 # endif 301 # if !defined(__IPHONE_5_1) 302 # define __IPHONE_5_1 50100 303 # endif 304 # if !defined(__IPHONE_6_0) 305 # define __IPHONE_6_0 60000 306 # endif 307 # if !defined(__IPHONE_6_1) 308 # define __IPHONE_6_1 60100 309 # endif 310 # if !defined(__IPHONE_7_0) 311 # define __IPHONE_7_0 70000 312 # endif 313 # if !defined(__IPHONE_7_1) 314 # define __IPHONE_7_1 70100 315 # endif 316 # if !defined(__IPHONE_8_0) 317 # define __IPHONE_8_0 80000 318 # endif 319 # if !defined(__IPHONE_8_1) 320 # define __IPHONE_8_1 80100 321 # endif 322 # if !defined(__IPHONE_8_2) 323 # define __IPHONE_8_2 80200 324 # endif 325 # if !defined(__IPHONE_8_3) 326 # define __IPHONE_8_3 80300 327 # endif 328 # if !defined(__IPHONE_8_4) 329 # define __IPHONE_8_4 80400 330 # endif 331 # if !defined(__IPHONE_9_0) 332 # define __IPHONE_9_0 90000 333 # endif 334 # if !defined(__IPHONE_9_1) 335 # define __IPHONE_9_1 90100 336 # endif 337 # if !defined(__IPHONE_9_2) 338 # define __IPHONE_9_2 90200 339 # endif 340 # if !defined(__IPHONE_9_3) 341 # define __IPHONE_9_3 90300 342 # endif 343 # if !defined(__IPHONE_10_0) 344 # define __IPHONE_10_0 100000 345 # endif 346 # if !defined(__IPHONE_10_1) 347 # define __IPHONE_10_1 100100 348 # endif 349 # if !defined(__IPHONE_10_2) 350 # define __IPHONE_10_2 100200 351 # endif 352 # if !defined(__IPHONE_10_3) 353 # define __IPHONE_10_3 100300 354 # endif 355 # if !defined(__IPHONE_11_0) 356 # define __IPHONE_11_0 110000 357 # endif 358 #endif 359 360 #ifdef __LSB_VERSION__ 361 # if __LSB_VERSION__ < 40 362 # error "This version of the Linux Standard Base is unsupported" 363 # endif 364 #ifndef QT_LINUXBASE 365 # define QT_LINUXBASE 366 #endif 367 #endif 368 369 #endif // QSYSTEMDETECTION_H
各种操作系统的宏定义。
【2】不同编译器不同版本的宏
（1）不同编译器
1.1 Visual C++ 编译器预定义宏：C/C++ Predefined Macros
1.2 GCC 编译器预定义宏：GNU Common Predefined Macros
（2）不同版本
2.1 Visual C++ 编译器 _MSC_VER
_MSC_VER 即时Microsoft C/C++ 编译器版本预定义宏。
一些编译器版本的_MSC_VER值：
1 MS VC++ 14.0 _MSC_VER = 1900 (Visual Studio 2015) 2 MS VC++ 12.0 _MSC_VER = 1800 (VisualStudio 2013) 3 MS VC++ 11.0 _MSC_VER = 1700 (VisualStudio 2012) 4 MS VC++ 10.0 _MSC_VER = 1600(VisualStudio 2010) 5 MS VC++ 9.0 _MSC_VER = 1500(VisualStudio 2008) 6 MS VC++ 8.0 _MSC_VER = 1400(VisualStudio 2005) 7 MS VC++ 7.1 _MSC_VER = 1310(VisualStudio 2003) 8 MS VC++ 7.0 _MSC_VER = 1300(VisualStudio .NET) 9 MS VC++ 6.0 _MSC_VER = 1200(VisualStudio 98) 10 MS VC++ 5.0 _MSC_VER = 1100(VisualStudio 97) 11 其中MS VC++ 14.0表示Visual C++的版本为14.0，后面括号中的Visual Studio 2015，表明该VC++包含在微软开发工具Visual Studio 2015中。
其应用示例如下：
1 #if _MSC_VER >= 1400 // for vc8, or vc9 2 #ifdef _DEBUG 3 #pragma comment( lib, "SomeLib-vc8-d.lib" ) 4 #elif 5 #pragma comment( lib, "SomeLib-vc8-r.lib" ) 6 #endif 7 #elif _MSC_VER >= 1310 // for vc71 8 #ifdef _DEBUG 9 #pragma comment( lib, "SomeLib-vc71-d.lib" ) 10 #elif 11 #pragma comment( lib, "SomeLib-vc71-r.lib" ) 12 #endif 13 #elif _MSC_VER >=1200 // for vc6 14 #ifdef _DEBUG 15 #pragma comment( lib, "SomeLib-vc6-d.lib" ) 16 #elif 17 #pragma comment( lib, "SomeLib-vc6-r.lib" ) 18 #endif 19 #endif
如上所述。
2.2 GCC编译器 _GNUC_
__GNUC__ 、__GNUC_MINOR__ 、__GNUC_PATCHLEVEL__分别代表gcc的主版本号，次版本号，修正版本号。
应用示例：比如我们的代码要求gcc的版本至少在3.2.0以上，我们就可以写成如下方式的条件编译：
1 /* Test for GCC > 3.2.0 */ 2 #if __GNUC__ > 3 || 3 (__GNUC__ == 3 && (__GNUC_MINOR__ > 2 || 4 (__GNUC_MINOR__ == 2 && 5 __GNUC_PATCHLEVEL__ > 0))) 6 printf("gcc > 3.2.0 "); 7 //... 8 #endif
Good Good Study, Day Day Up.
顺序 选择 循环 总结