1 //===- lib/Support/ErrorHandling.cpp - Callbacks for errors ---------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines an API used to indicate fatal error conditions. Non-fatal
11 // errors (most of them) should be handled through LLVMContext.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Support/ErrorHandling.h"
16 #include "llvm-c/Core.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/Twine.h"
19 #include "llvm/Config/config.h"
20 #include "llvm/Support/Debug.h"
21 #include "llvm/Support/Signals.h"
22 #include "llvm/Support/Mutex.h"
23 #include "llvm/Support/MutexGuard.h"
24 #include "llvm/Support/Threading.h"
25 #include "llvm/Support/raw_ostream.h"
29 #if defined(HAVE_UNISTD_H)
39 static fatal_error_handler_t ErrorHandler = nullptr;
40 static void *ErrorHandlerUserData = nullptr;
42 static sys::Mutex ErrorHandlerMutex;
44 void llvm::install_fatal_error_handler(fatal_error_handler_t handler,
46 llvm::MutexGuard Lock(ErrorHandlerMutex);
47 assert(!ErrorHandler && "Error handler already registered!\n");
48 ErrorHandler = handler;
49 ErrorHandlerUserData = user_data;
52 void llvm::remove_fatal_error_handler() {
53 llvm::MutexGuard Lock(ErrorHandlerMutex);
54 ErrorHandler = nullptr;
55 ErrorHandlerUserData = nullptr;
58 void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) {
59 report_fatal_error(Twine(Reason), GenCrashDiag);
62 void llvm::report_fatal_error(const std::string &Reason, bool GenCrashDiag) {
63 report_fatal_error(Twine(Reason), GenCrashDiag);
66 void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) {
67 report_fatal_error(Twine(Reason), GenCrashDiag);
70 void llvm::report_fatal_error(const Twine &Reason, bool GenCrashDiag) {
71 llvm::fatal_error_handler_t handler = nullptr;
72 void* handlerData = nullptr;
74 // Only acquire the mutex while reading the handler, so as not to invoke a
75 // user-supplied callback under a lock.
76 llvm::MutexGuard Lock(ErrorHandlerMutex);
77 handler = ErrorHandler;
78 handlerData = ErrorHandlerUserData;
82 handler(handlerData, Reason.str(), GenCrashDiag);
84 // Blast the result out to stderr. We don't try hard to make sure this
85 // succeeds (e.g. handling EINTR) and we can't use errs() here because
86 // raw ostreams can call report_fatal_error.
87 SmallVector<char, 64> Buffer;
88 raw_svector_ostream OS(Buffer);
89 OS << "LLVM ERROR: " << Reason << "\n";
90 StringRef MessageStr = OS.str();
91 ssize_t written = ::write(2, MessageStr.data(), MessageStr.size());
92 (void)written; // If something went wrong, we deliberately just give up.
95 // If we reached here, we are failing ungracefully. Run the interrupt handlers
96 // to make sure any special cleanups get done, in particular that we remove
97 // files registered with RemoveFileOnSignal.
98 sys::RunInterruptHandlers();
103 void llvm::llvm_unreachable_internal(const char *msg, const char *file,
105 // This code intentionally doesn't call the ErrorHandler callback, because
106 // llvm_unreachable is intended to be used to indicate "impossible"
107 // situations, and not legitimate runtime errors.
109 dbgs() << msg << "\n";
110 dbgs() << "UNREACHABLE executed";
112 dbgs() << " at " << file << ":" << line;
115 #ifdef LLVM_BUILTIN_UNREACHABLE
116 // Windows systems and possibly others don't declare abort() to be noreturn,
117 // so use the unreachable builtin to avoid a Clang self-host warning.
118 LLVM_BUILTIN_UNREACHABLE;
122 static void bindingsErrorHandler(void *user_data, const std::string& reason,
123 bool gen_crash_diag) {
124 LLVMFatalErrorHandler handler =
125 LLVM_EXTENSION reinterpret_cast<LLVMFatalErrorHandler>(user_data);
126 handler(reason.c_str());
129 void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) {
130 install_fatal_error_handler(bindingsErrorHandler,
131 LLVM_EXTENSION reinterpret_cast<void *>(Handler));
134 void LLVMResetFatalErrorHandler() {
135 remove_fatal_error_handler();