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3 | ** Copyright (C) 2016 Intel Corporation. |
4 | ** Contact: https://www.qt.io/licensing/ |
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38 | ****************************************************************************/ |
39 | |
40 | // qglobal.h includes this header, so keep it outside of our include guards |
41 | #include <QtCore/qglobal.h> |
42 | |
43 | #if !defined(QVERSIONTAGGING_H) |
44 | #define QVERSIONTAGGING_H |
45 | |
46 | QT_BEGIN_NAMESPACE |
47 | |
48 | /* |
49 | * Ugly hack warning and explanation: |
50 | * |
51 | * This file causes all ELF modules, be they libraries or applications, to use the |
52 | * qt_version_tag symbol that is present in QtCore. Such symbol is versioned, |
53 | * so the linker will automatically pull the current Qt version and add it to |
54 | * the ELF header of the library/application. The assembly produces one section |
55 | * called ".qtversion" containing two 32-bit values. The first is a |
56 | * relocation to the qt_version_tag symbol (which is what causes the ELF |
57 | * version to get used). The second value is the current Qt version at the time |
58 | * of compilation. |
59 | * |
60 | * There will only be one copy of the section in the output library or application. |
61 | */ |
62 | |
63 | #if defined(QT_BUILD_CORE_LIB) || defined(QT_BOOTSTRAPPED) || defined(QT_NO_VERSION_TAGGING) || defined(QT_STATIC) |
64 | // don't make tags in QtCore, bootstrapped systems or if the user asked not to |
65 | #elif defined(Q_CC_GNU) && !defined(Q_OS_ANDROID) |
66 | # if defined(Q_PROCESSOR_X86) && (defined(Q_OS_LINUX) || defined(Q_OS_FREEBSD_KERNEL)) |
67 | # if defined(Q_PROCESSOR_X86_64) && QT_POINTER_SIZE == 8 // x86-64 64-bit |
68 | # define QT_VERSION_TAG_RELOC(sym) ".quad " QT_STRINGIFY(QT_MANGLE_NAMESPACE(sym)) "@GOT\n" |
69 | # else // x86 or x86-64 32-bit (x32) |
70 | # define QT_VERSION_TAG_RELOC(sym) ".long " QT_STRINGIFY(QT_MANGLE_NAMESPACE(sym)) "@GOT\n" |
71 | # endif |
72 | # define QT_VERSION_TAG(sym) \ |
73 | asm ( \ |
74 | ".section .qtversion, \"aG\", @progbits, " QT_STRINGIFY(QT_MANGLE_NAMESPACE(sym)) ", comdat\n" \ |
75 | ".align 8\n" \ |
76 | QT_VERSION_TAG_RELOC(sym) \ |
77 | ".long " QT_STRINGIFY(QT_VERSION) "\n" \ |
78 | ".align 8\n" \ |
79 | ".previous" \ |
80 | ) |
81 | # endif |
82 | #endif |
83 | |
84 | #if defined(QT_VERSION_TAG) |
85 | QT_VERSION_TAG(qt_version_tag); |
86 | #endif |
87 | |
88 | QT_END_NAMESPACE |
89 | |
90 | #endif // QVERSIONTAGGING_H |
91 | |