-//===- llvm/Support/ErrorHandling.h - Callbacks for errors ------*- C++ -*-===//
+//===- llvm/Support/ErrorHandling.h - Fatal error handling ------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
//
-// This file defines an API used to indicate error conditions.
-// Callbacks can be registered for these errors through this API.
+// This file defines an API used to indicate fatal error conditions. Non-fatal
+// errors (most of them) should be handled through LLVMContext.
//
//===----------------------------------------------------------------------===//
class Twine;
/// An error handler callback.
- typedef void (*llvm_error_handler_t)(void *user_data,
- const std::string& reason);
+ typedef void (*fatal_error_handler_t)(void *user_data,
+ const std::string& reason);
- /// llvm_instal_error_handler - Installs a new error handler to be used
+ /// install_fatal_error_handler - Installs a new error handler to be used
/// whenever a serious (non-recoverable) error is encountered by LLVM.
///
/// If you are using llvm_start_multithreaded, you should register the handler
/// printed to stderr. If the error handler returns, then exit(1) will be
/// called.
///
+ /// It is dangerous to naively use an error handler which throws an exception.
+ /// Even though some applications desire to gracefully recover from arbitrary
+ /// faults, blindly throwing exceptions through unfamiliar code isn't a way to
+ /// achieve this.
+ ///
/// \param user_data - An argument which will be passed to the install error
/// handler.
- void llvm_install_error_handler(llvm_error_handler_t handler,
- void *user_data = 0);
+ void install_fatal_error_handler(fatal_error_handler_t handler,
+ void *user_data = 0);
/// Restores default error handling behaviour.
/// This must not be called between llvm_start_multithreaded() and
/// llvm_stop_multithreaded().
- void llvm_remove_error_handler(void);
+ void remove_fatal_error_handler();
+
+ /// ScopedFatalErrorHandler - This is a simple helper class which just
+ /// calls install_fatal_error_handler in its constructor and
+ /// remove_fatal_error_handler in its destructor.
+ struct ScopedFatalErrorHandler {
+ explicit ScopedFatalErrorHandler(fatal_error_handler_t handler,
+ void *user_data = 0) {
+ install_fatal_error_handler(handler, user_data);
+ }
+
+ ~ScopedFatalErrorHandler() { remove_fatal_error_handler(); }
+ };
- /// Reports a serious error, calling any installed error handler.
+ /// Reports a serious error, calling any installed error handler. These
+ /// functions are intended to be used for error conditions which are outside
+ /// the control of the compiler (I/O errors, invalid user input, etc.)
+ ///
/// If no error handler is installed the default is to print the message to
/// standard error, followed by a newline.
/// After the error handler is called this function will call exit(1), it
/// does not return.
- void llvm_report_error(const char *reason) NORETURN;
- void llvm_report_error(const std::string &reason) NORETURN;
- void llvm_report_error(const Twine &reason) NORETURN;
+ NORETURN void report_fatal_error(const char *reason);
+ NORETURN void report_fatal_error(const std::string &reason);
+ NORETURN void report_fatal_error(const Twine &reason);
/// This function calls abort(), and prints the optional message to stderr.
/// Use the llvm_unreachable macro (that adds location info), instead of
/// calling this function directly.
- void llvm_unreachable_internal(const char *msg=0, const char *file=0,
- unsigned line=0) NORETURN;
+ NORETURN void llvm_unreachable_internal(const char *msg=0,
+ const char *file=0, unsigned line=0);
}
/// Prints the message and location info to stderr in !NDEBUG builds.
+/// This is intended to be used for "impossible" situations that imply
+/// a bug in the compiler.
+///
/// In NDEBUG mode it only prints "UNREACHABLE executed".
/// Use this instead of assert(0), so that the compiler knows this path
/// is not reachable even for NDEBUG builds.
#ifndef NDEBUG
-#define llvm_unreachable(msg) llvm_unreachable_internal(msg, __FILE__, __LINE__)
+#define llvm_unreachable(msg) \
+ ::llvm::llvm_unreachable_internal(msg, __FILE__, __LINE__)
#else
-#define llvm_unreachable(msg) llvm_unreachable_internal()
+#define llvm_unreachable(msg) ::llvm::llvm_unreachable_internal()
#endif
#endif
-