// Copyright (C) 2022 The Qt Company Ltd. // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only #include "qassert.h" #include #include #include #include #ifndef QT_NO_EXCEPTIONS #include #endif #if defined(Q_CC_MSVC) # include #endif #ifdef Q_OS_WIN # include #endif QT_BEGIN_NAMESPACE void qAbort() { #ifdef Q_OS_WIN // std::abort() in the MSVC runtime will call _exit(3) if the abort // behavior is _WRITE_ABORT_MSG - see also _set_abort_behavior(). This is // the default for a debug-mode build of the runtime. Worse, MinGW's // std::abort() implementation (in msvcrt.dll) is basically a call to // _exit(3) too. Unfortunately, _exit() and _Exit() *do* run the static // destructors of objects in DLLs, a violation of the C++ standard (see // [support.start.term]). So we bypass std::abort() and directly // terminate the application. # if defined(Q_CC_MSVC) if (IsProcessorFeaturePresent(PF_FASTFAIL_AVAILABLE)) __fastfail(FAST_FAIL_FATAL_APP_EXIT); # else RaiseFailFastException(nullptr, nullptr, 0); # endif // Fallback TerminateProcess(GetCurrentProcess(), STATUS_FATAL_APP_EXIT); // Tell the compiler the application has stopped. Q_UNREACHABLE_IMPL(); #else // !Q_OS_WIN std::abort(); #endif } /*! \macro void Q_ASSERT(bool test) \relates Prints a warning message containing the source code file name and line number if \a test is \c false. Q_ASSERT() is useful for testing pre- and post-conditions during development. It does nothing if \c QT_NO_DEBUG was defined during compilation. Example: \snippet code/src_corelib_global_qglobal.cpp 17 If \c b is zero, the Q_ASSERT statement will output the following message using the qFatal() function: \snippet code/src_corelib_global_qglobal.cpp 18 \sa Q_ASSERT_X(), qFatal(), {Debugging Techniques} */ /*! \macro void Q_ASSERT_X(bool test, const char *where, const char *what) \relates Prints the message \a what together with the location \a where, the source file name and line number if \a test is \c false. Q_ASSERT_X is useful for testing pre- and post-conditions during development. It does nothing if \c QT_NO_DEBUG was defined during compilation. Example: \snippet code/src_corelib_global_qglobal.cpp 19 If \c b is zero, the Q_ASSERT_X statement will output the following message using the qFatal() function: \snippet code/src_corelib_global_qglobal.cpp 20 \sa Q_ASSERT(), qFatal(), {Debugging Techniques} */ /* The Q_ASSERT macro calls this function when the test fails. */ void qt_assert(const char *assertion, const char *file, int line) noexcept { QMessageLogger(file, line, nullptr) .fatal("ASSERT: \"%s\" in file %s, line %d", assertion, file, line); } /* The Q_ASSERT_X macro calls this function when the test fails. */ void qt_assert_x(const char *where, const char *what, const char *file, int line) noexcept { QMessageLogger(file, line, nullptr) .fatal("ASSERT failure in %s: \"%s\", file %s, line %d", where, what, file, line); } /*! \macro void Q_CHECK_PTR(void *pointer) \relates If \a pointer is \nullptr, prints a message containing the source code's file name and line number, saying that the program ran out of memory and aborts program execution. It throws \c std::bad_alloc instead if exceptions are enabled. Q_CHECK_PTR does nothing if \c QT_NO_DEBUG and \c QT_NO_EXCEPTIONS were defined during compilation. Therefore you must not use Q_CHECK_PTR to check for successful memory allocations because the check will be disabled in some cases. Example: \snippet code/src_corelib_global_qglobal.cpp 21 \sa qWarning(), {Debugging Techniques} */ /*! \fn template T *q_check_ptr(T *p) \relates Uses Q_CHECK_PTR on \a p, then returns \a p. This can be used as an inline version of Q_CHECK_PTR. */ /*! \internal The Q_CHECK_PTR macro calls this function if an allocation check fails. */ void qt_check_pointer(const char *n, int l) noexcept { // make separate printing calls so that the first one may flush; // the second one could want to allocate memory (fputs prints a // newline and stderr auto-flushes). fputs("Out of memory", stderr); fprintf(stderr, " in %s, line %d\n", n, l); std::terminate(); } /* \internal Allows you to throw an exception without including Called internally from Q_CHECK_PTR on certain OS combinations */ void qBadAlloc() { #ifndef QT_NO_EXCEPTIONS throw std::bad_alloc(); #else std::terminate(); #endif } /*! \macro void Q_ASSUME(bool expr) \deprecated \relates \since 5.0 Causes the compiler to assume that \a expr is \c true. This macro is known to produce worse code than when no assumption was inserted in the code, with some compiler versions. The arguments passed to it are always evaluated, even in release mode, with some compilers and not others, so application code needs to be aware of those possible differences in behavior. Do not use it in new code. It is retained as-is for compatibility with old code and will likely be removed in the next major version Qt. \sa Q_ASSERT(), Q_UNREACHABLE(), Q_LIKELY() */ /*! \macro QT_TERMINATE_ON_EXCEPTION(expr) \relates \internal In general, use of the Q_DECL_NOEXCEPT macro is preferred over Q_DECL_NOTHROW, because it exhibits well-defined behavior and supports the more powerful Q_DECL_NOEXCEPT_EXPR variant. However, use of Q_DECL_NOTHROW has the advantage that Windows builds benefit on a wide range or compiler versions that do not yet support the C++11 noexcept feature. It may therefore be beneficial to use Q_DECL_NOTHROW and emulate the C++11 behavior manually with an embedded try/catch. Qt provides the QT_TERMINATE_ON_EXCEPTION(expr) macro for this purpose. It either expands to \c expr (if Qt is compiled without exception support or the compiler supports C++11 noexcept semantics) or to \snippet code/src_corelib_global_qglobal.cpp qterminate otherwise. Since this macro expands to just \c expr if the compiler supports C++11 noexcept, expecting the compiler to take over responsibility of calling std::terminate() in that case, it should not be used outside Q_DECL_NOTHROW functions. \sa Q_DECL_NOEXCEPT, Q_DECL_NOTHROW, qTerminate() */ /*! \macro void Q_UNREACHABLE() \relates \since 5.0 Tells the compiler that the current point cannot be reached by any execution, so it may optimize any code paths leading here as dead code, as well as code continuing from here. This macro is useful to mark impossible conditions. For example, given the following enum: \snippet code/src_corelib_global_qglobal.cpp qunreachable-enum One can write a switch table like so: \snippet code/src_corelib_global_qglobal.cpp qunreachable-switch The advantage of inserting Q_UNREACHABLE() at that point is that the compiler is told not to generate code for a shape variable containing that value. If the macro is missing, the compiler will still generate the necessary comparisons for that value. If the case label were removed, some compilers could produce a warning that some enum values were not checked. By using this macro in impossible conditions, code coverage may be improved as dead code paths may be eliminated. In debug builds the condition is enforced by an assert to facilitate debugging. \note Use the macro Q_UNREACHABLE_RETURN() to insert return statements for compilers that need them, without causing warnings for compilers that complain about its presence. \sa Q_ASSERT(), qFatal(), Q_UNREACHABLE_RETURN() */ /*! \macro void Q_UNREACHABLE_RETURN(...) \relates \since 6.5 This is equivalent to \code Q_UNREACHABLE(); return __VA_ARGS__; \endcode except it omits the return on compilers that would warn about it. \sa Q_UNREACHABLE() */ QT_END_NAMESPACE