diff options
Diffstat (limited to 'lib/std')
| -rw-r--r-- | lib/std/builtin.zig | 2 | ||||
| -rw-r--r-- | lib/std/debug.zig | 46 |
2 files changed, 39 insertions, 9 deletions
diff --git a/lib/std/builtin.zig b/lib/std/builtin.zig index f01e7605ab..c0d2e9f725 100644 --- a/lib/std/builtin.zig +++ b/lib/std/builtin.zig @@ -710,7 +710,7 @@ pub fn default_panic(msg: []const u8, error_return_trace: ?*StackTrace) noreturn }, else => { const first_trace_addr = @returnAddress(); - std.debug.panicExtra(error_return_trace, first_trace_addr, "{s}", .{msg}); + std.debug.panicImpl(error_return_trace, first_trace_addr, msg); }, } } diff --git a/lib/std/debug.zig b/lib/std/debug.zig index 6e2cef1f0c..2194886c0a 100644 --- a/lib/std/debug.zig +++ b/lib/std/debug.zig @@ -228,9 +228,32 @@ pub fn assert(ok: bool) void { pub fn panic(comptime format: []const u8, args: anytype) noreturn { @setCold(true); - // TODO: remove conditional once wasi / LLVM defines __builtin_return_address - const first_trace_addr = if (native_os == .wasi) null else @returnAddress(); - panicExtra(null, first_trace_addr, format, args); + + panicExtra(null, format, args); +} + +/// `panicExtra` is useful when you want to print out an `@errorReturnTrace` +/// and also print out some values. +pub fn panicExtra( + trace: ?*builtin.StackTrace, + comptime format: []const u8, + args: anytype, +) noreturn { + @setCold(true); + + const size = 0x1000; + const trunc_msg = "(msg truncated)"; + var buf: [size + trunc_msg.len]u8 = undefined; + // a minor annoyance with this is that it will result in the NoSpaceLeft + // error being part of the @panic stack trace (but that error should + // only happen rarely) + const msg = std.fmt.bufPrint(buf[0..size], format, args) catch |err| switch (err) { + std.fmt.BufPrintError.NoSpaceLeft => blk: { + std.mem.copy(u8, buf[size..], trunc_msg); + break :blk &buf; + }, + }; + builtin.panic(msg, trace); } /// Non-zero whenever the program triggered a panic. @@ -244,7 +267,9 @@ var panic_mutex = std.Thread.Mutex{}; /// This is used to catch and handle panics triggered by the panic handler. threadlocal var panic_stage: usize = 0; -pub fn panicExtra(trace: ?*const builtin.StackTrace, first_trace_addr: ?usize, comptime format: []const u8, args: anytype) noreturn { +// `panicImpl` could be useful in implementing a custom panic handler which +// calls the default handler (on supported platforms) +pub fn panicImpl(trace: ?*const builtin.StackTrace, first_trace_addr: ?usize, msg: []const u8) noreturn { @setCold(true); if (enable_segfault_handler) { @@ -271,7 +296,7 @@ pub fn panicExtra(trace: ?*const builtin.StackTrace, first_trace_addr: ?usize, c const current_thread_id = std.Thread.getCurrentId(); stderr.print("thread {} panic: ", .{current_thread_id}) catch os.abort(); } - stderr.print(format ++ "\n", args) catch os.abort(); + stderr.print("{s}\n", .{msg}) catch os.abort(); if (trace) |t| { dumpStackTrace(t.*); } @@ -1626,9 +1651,14 @@ fn handleSegfaultWindowsExtra(info: *windows.EXCEPTION_POINTERS, comptime msg: u os.abort(); } else { switch (msg) { - 0 => panicExtra(null, exception_address, format.?, .{}), - 1 => panicExtra(null, exception_address, "Segmentation fault at address 0x{x}", .{info.ExceptionRecord.ExceptionInformation[1]}), - 2 => panicExtra(null, exception_address, "Illegal Instruction", .{}), + 0 => panicImpl(null, exception_address, format.?), + 1 => { + const format_item = "Segmentation fault at address 0x{x}"; + var buf: [format_item.len + 64]u8 = undefined; // 64 is arbitrary, but sufficiently large + const to_print = std.fmt.bufPrint(buf[0..buf.len], format_item, .{info.ExceptionRecord.ExceptionInformation[1]}) catch unreachable; + panicImpl(null, exception_address, to_print); + }, + 2 => panicImpl(null, exception_address, "Illegal Instruction"), else => unreachable, } } |