Bring back btjs (#18108)

2026-02-15 21:32:05 +00:00 · 2025-03-11 22:51:05 -07:00
parent 29870cb572
commit 5c7df736bf
11 changed files with 280 additions and 46 deletions
--- a/.lldbinit
+++ b/.lldbinit
@@ -1,4 +1,16 @@
-# command script import vendor/zig/tools/lldb_pretty_printers.py
-command script import vendor/WebKit/Tools/lldb/lldb_webkit.py
+# Tell LLDB what to do when the debugged process receives SIGPWR: pass it through to the process
+# (-p), but do not stop the process (-s) or notify the user (-n).
+#
+# JSC's garbage collector sends this signal (as configured by Bun WebKit in
+# Thread::initializePlatformThreading() in ThreadingPOSIX.cpp) to the JS thread to suspend or resume
+# it. So stopping the process would just create noise when debugging any long-running script.
+process handle -p true -s false -n false SIGPWR

-# type summary add --summary-string "${var} | inner=${var[0-30]}, source=${var[33-64]}, tag=${var[31-32]}" "unsigned long"
+command script import misctools/lldb/lldb_pretty_printers.py
+type category enable zig.lang
+type category enable zig.std
+
+command script import misctools/lldb/lldb_webkit.py
+
+command script delete btjs
+command alias btjs p {printf("gathering btjs trace...\n");printf("%s\n", (char*)dumpBtjsTrace())}
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -22,7 +22,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -38,7 +37,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -60,7 +58,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -76,7 +73,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -92,7 +88,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -108,7 +103,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -125,7 +119,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
      "serverReadyAction": {
        "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
        "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -147,7 +140,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
      "serverReadyAction": {
        "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
        "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -169,7 +161,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -188,7 +179,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -203,7 +193,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -221,7 +210,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -236,7 +224,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -253,7 +240,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
      "serverReadyAction": {
        "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
        "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -275,7 +261,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
      "serverReadyAction": {
        "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
        "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -297,7 +282,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -313,7 +297,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -329,7 +312,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -345,7 +327,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -361,7 +342,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -378,7 +358,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
      "serverReadyAction": {
        "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
        "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -400,7 +379,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
      "serverReadyAction": {
        "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
        "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -421,7 +399,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    // bun test [*]
    {
@@ -437,7 +414,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -452,7 +428,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -468,7 +443,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
      "serverReadyAction": {
        "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
        "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -488,7 +462,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "lldb",
@@ -503,7 +476,6 @@
      },
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    // Windows: bun test [file]
    {
@@ -1129,7 +1101,6 @@
      ],
      "console": "internalConsole",
      // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
    },
    {
      "type": "bun",
--- a/misctools/lldb/lldb_commands
+++ b/misctools/lldb/lldb_commands
@@ -1,13 +0,0 @@
-# Tell LLDB what to do when the debugged process receives SIGPWR: pass it through to the process
-# (-p), but do not stop the process (-s) or notify the user (-n).
-#
-# JSC's garbage collector sends this signal (as configured by Bun WebKit in
-# Thread::initializePlatformThreading() in ThreadingPOSIX.cpp) to the JS thread to suspend or resume
-# it. So stopping the process would just create noise when debugging any long-running script.
-process handle -p true -s false -n false SIGPWR
-
-command script import misctools/lldb/lldb_pretty_printers.py
-type category enable zig.lang
-type category enable zig.std
-
-command script import misctools/lldb/lldb_webkit.py
--- a/misctools/lldb/lldb_webkit.py
+++ b/misctools/lldb/lldb_webkit.py
@@ -329,7 +329,7 @@ def btjs(debugger, command, result, internal_dict):
    addressFormat = '#0{width}x'.format(width=target.GetAddressByteSize() * 2 + 2)
    process = target.GetProcess()
    thread = process.GetSelectedThread()
-    jscModule = target.module["JavaScriptCore"]
+    jscModule = target.module["JavaScriptCore"] or target.module["bun"] or target.module["bun-debug"]

    if jscModule.FindSymbol("JSC::CallFrame::describeFrame").GetSize() or jscModule.FindSymbol("_ZN3JSC9CallFrame13describeFrameEv").GetSize():
        annotateJSFrames = True
--- a/src/btjs.zig
+++ b/src/btjs.zig
@@ -0,0 +1,248 @@
+const std = @import("std");
+const bun = @import("root").bun;
+
+extern const jsc_llint_begin: u8;
+extern const jsc_llint_end: u8;
+/// allocated using bun.default_allocator. when called from lldb, it is never freed.
+pub export fn dumpBtjsTrace() [*:0]const u8 {
+    if (@import("builtin").mode != .Debug) return "dumpBtjsTrace is disabled in release builds";
+
+    var result_writer = std.ArrayList(u8).init(bun.default_allocator);
+    const w = result_writer.writer();
+
+    const debug_info = std.debug.getSelfDebugInfo() catch |err| {
+        w.print("Unable to dump stack trace: Unable to open debug info: {s}\x00", .{@errorName(err)}) catch {
+            result_writer.deinit();
+            return "<oom>".ptr;
+        };
+        return @ptrCast((result_writer.toOwnedSlice() catch {
+            result_writer.deinit();
+            return "<oom>".ptr;
+        }).ptr);
+    };
+
+    // std.log.info("jsc_llint_begin: {x}", .{@intFromPtr(&jsc_llint_begin)});
+    // std.log.info("jsc_llint_end: {x}", .{@intFromPtr(&jsc_llint_end)});
+
+    const tty_config = std.io.tty.detectConfig(std.io.getStdOut());
+
+    var context: std.debug.ThreadContext = undefined;
+    const has_context = std.debug.getContext(&context);
+
+    var it: std.debug.StackIterator = (if (has_context) blk: {
+        break :blk std.debug.StackIterator.initWithContext(null, debug_info, &context) catch null;
+    } else null) orelse std.debug.StackIterator.init(null, null);
+    defer it.deinit();
+
+    while (it.next()) |return_address| {
+        printLastUnwindError(&it, debug_info, w, tty_config);
+
+        // On arm64 macOS, the address of the last frame is 0x0 rather than 0x1 as on x86_64 macOS,
+        // therefore, we do a check for `return_address == 0` before subtracting 1 from it to avoid
+        // an overflow. We do not need to signal `StackIterator` as it will correctly detect this
+        // condition on the subsequent iteration and return `null` thus terminating the loop.
+        // same behaviour for x86-windows-msvc
+        const address = return_address -| 1;
+        printSourceAtAddress(debug_info, w, address, tty_config, it.fp) catch {};
+    } else {
+        printLastUnwindError(&it, debug_info, w, tty_config);
+    }
+
+    // remove nulls
+    for (result_writer.items) |*itm| if (itm.* == 0) {
+        itm.* = ' ';
+    };
+    // add null terminator
+    result_writer.append(0) catch {
+        result_writer.deinit();
+        return "<oom>".ptr;
+    };
+    return @ptrCast((result_writer.toOwnedSlice() catch {
+        result_writer.deinit();
+        return "<oom>".ptr;
+    }).ptr);
+}
+
+pub fn printSourceAtAddress(debug_info: *std.debug.SelfInfo, out_stream: anytype, address: usize, tty_config: std.io.tty.Config, fp: usize) !void {
+    const module = debug_info.getModuleForAddress(address) catch |err| switch (err) {
+        error.MissingDebugInfo, error.InvalidDebugInfo => return printUnknownSource(debug_info, out_stream, address, tty_config),
+        else => return err,
+    };
+
+    const symbol_info = module.getSymbolAtAddress(debug_info.allocator, address) catch |err| switch (err) {
+        error.MissingDebugInfo, error.InvalidDebugInfo => return printUnknownSource(debug_info, out_stream, address, tty_config),
+        else => return err,
+    };
+    defer if (symbol_info.source_location) |sl| debug_info.allocator.free(sl.file_name);
+
+    const probably_llint = address > @intFromPtr(&jsc_llint_begin) and address < @intFromPtr(&jsc_llint_end);
+    var allow_llint = true;
+    if (std.mem.startsWith(u8, symbol_info.name, "__")) {
+        allow_llint = false; // disallow llint for __ZN3JSC11Interpreter20executeModuleProgramEPNS_14JSModuleRecordEPNS_23ModuleProgramExecutableEPNS_14JSGlobalObjectEPNS_19JSModuleEnvironmentENS_7JSValueES9_
+    }
+    if (std.mem.startsWith(u8, symbol_info.name, "_llint_call_javascript")) {
+        allow_llint = false; // disallow llint for _llint_call_javascript
+    }
+    const do_llint = probably_llint and allow_llint;
+
+    const frame: *const bun.JSC.CallFrame = @ptrFromInt(fp);
+    if (do_llint) {
+        const srcloc = frame.getCallerSrcLoc(bun.JSC.Bun__getVM().global);
+        try tty_config.setColor(out_stream, .bold);
+        try out_stream.print("{s}:{d}:{d}: ", .{ srcloc.str, srcloc.line, srcloc.column });
+        try tty_config.setColor(out_stream, .reset);
+    }
+
+    try printLineInfo(
+        out_stream,
+        symbol_info.source_location,
+        address,
+        symbol_info.name,
+        symbol_info.compile_unit_name,
+        tty_config,
+        printLineFromFileAnyOs,
+        do_llint,
+    );
+    if (do_llint) {
+        const desc = frame.describeFrame();
+        try out_stream.print("    {s}\n    ", .{desc});
+        try tty_config.setColor(out_stream, .green);
+        try out_stream.writeAll("^");
+        try tty_config.setColor(out_stream, .reset);
+        try out_stream.writeAll("\n");
+    }
+}
+
+fn printUnknownSource(debug_info: *std.debug.SelfInfo, out_stream: anytype, address: usize, tty_config: std.io.tty.Config) !void {
+    const module_name = debug_info.getModuleNameForAddress(address);
+    return printLineInfo(
+        out_stream,
+        null,
+        address,
+        "???",
+        module_name orelse "???",
+        tty_config,
+        printLineFromFileAnyOs,
+        false,
+    );
+}
+fn printLineInfo(
+    out_stream: anytype,
+    source_location: ?std.debug.SourceLocation,
+    address: usize,
+    symbol_name: []const u8,
+    compile_unit_name: []const u8,
+    tty_config: std.io.tty.Config,
+    comptime printLineFromFile: anytype,
+    do_llint: bool,
+) !void {
+    nosuspend {
+        try tty_config.setColor(out_stream, .bold);
+
+        if (source_location) |*sl| {
+            try out_stream.print("{s}:{d}:{d}", .{ sl.file_name, sl.line, sl.column });
+        } else if (!do_llint) {
+            try out_stream.writeAll("???:?:?");
+        }
+
+        try tty_config.setColor(out_stream, .reset);
+        if (!do_llint or source_location != null) try out_stream.writeAll(": ");
+        try tty_config.setColor(out_stream, .dim);
+        try out_stream.print("0x{x} in {s} ({s})", .{ address, symbol_name, compile_unit_name });
+        try tty_config.setColor(out_stream, .reset);
+        try out_stream.writeAll("\n");
+
+        // Show the matching source code line if possible
+        if (source_location) |sl| {
+            if (printLineFromFile(out_stream, sl)) {
+                if (sl.column > 0) {
+                    // The caret already takes one char
+                    const space_needed = @as(usize, @intCast(sl.column - 1));
+
+                    try out_stream.writeByteNTimes(' ', space_needed);
+                    try tty_config.setColor(out_stream, .green);
+                    try out_stream.writeAll("^");
+                    try tty_config.setColor(out_stream, .reset);
+                }
+                try out_stream.writeAll("\n");
+            } else |err| switch (err) {
+                error.EndOfFile, error.FileNotFound => {},
+                error.BadPathName => {},
+                error.AccessDenied => {},
+                else => return err,
+            }
+        }
+    }
+}
+
+fn printLineFromFileAnyOs(out_stream: anytype, source_location: std.debug.SourceLocation) !void {
+    // Need this to always block even in async I/O mode, because this could potentially
+    // be called from e.g. the event loop code crashing.
+    var f = try std.fs.cwd().openFile(source_location.file_name, .{});
+    defer f.close();
+    // TODO fstat and make sure that the file has the correct size
+
+    var buf: [std.mem.page_size]u8 = undefined;
+    var amt_read = try f.read(buf[0..]);
+    const line_start = seek: {
+        var current_line_start: usize = 0;
+        var next_line: usize = 1;
+        while (next_line != source_location.line) {
+            const slice = buf[current_line_start..amt_read];
+            if (std.mem.indexOfScalar(u8, slice, '\n')) |pos| {
+                next_line += 1;
+                if (pos == slice.len - 1) {
+                    amt_read = try f.read(buf[0..]);
+                    current_line_start = 0;
+                } else current_line_start += pos + 1;
+            } else if (amt_read < buf.len) {
+                return error.EndOfFile;
+            } else {
+                amt_read = try f.read(buf[0..]);
+                current_line_start = 0;
+            }
+        }
+        break :seek current_line_start;
+    };
+    const slice = buf[line_start..amt_read];
+    if (std.mem.indexOfScalar(u8, slice, '\n')) |pos| {
+        const line = slice[0 .. pos + 1];
+        std.mem.replaceScalar(u8, line, '\t', ' ');
+        return out_stream.writeAll(line);
+    } else { // Line is the last inside the buffer, and requires another read to find delimiter. Alternatively the file ends.
+        std.mem.replaceScalar(u8, slice, '\t', ' ');
+        try out_stream.writeAll(slice);
+        while (amt_read == buf.len) {
+            amt_read = try f.read(buf[0..]);
+            if (std.mem.indexOfScalar(u8, buf[0..amt_read], '\n')) |pos| {
+                const line = buf[0 .. pos + 1];
+                std.mem.replaceScalar(u8, line, '\t', ' ');
+                return out_stream.writeAll(line);
+            } else {
+                const line = buf[0..amt_read];
+                std.mem.replaceScalar(u8, line, '\t', ' ');
+                try out_stream.writeAll(line);
+            }
+        }
+        // Make sure printing last line of file inserts extra newline
+        try out_stream.writeByte('\n');
+    }
+}
+
+fn printLastUnwindError(it: *std.debug.StackIterator, debug_info: *std.debug.SelfInfo, out_stream: anytype, tty_config: std.io.tty.Config) void {
+    if (!std.debug.have_ucontext) return;
+    if (it.getLastError()) |unwind_error| {
+        printUnwindError(debug_info, out_stream, unwind_error.address, unwind_error.err, tty_config) catch {};
+    }
+}
+
+fn printUnwindError(debug_info: *std.debug.SelfInfo, out_stream: anytype, address: usize, err: std.debug.UnwindError, tty_config: std.io.tty.Config) !void {
+    const module_name = debug_info.getModuleNameForAddress(address) orelse "???";
+    try tty_config.setColor(out_stream, .dim);
+    if (err == error.MissingDebugInfo) {
+        try out_stream.print("Unwind information for `{s}:0x{x}` was not available, trace may be incomplete\n\n", .{ module_name, address });
+    } else {
+        try out_stream.print("Unwind error at address `{s}:0x{x}` ({}), trace may be incomplete\n\n", .{ module_name, address, err });
+    }
+    try tty_config.setColor(out_stream, .reset);
+}
--- a/src/bun.js/api/BunObject.zig
+++ b/src/bun.js/api/BunObject.zig
@@ -4823,6 +4823,7 @@ const InternalTestingAPIs = struct {

 comptime {
    _ = Crypto.JSPasswordObject.JSPasswordObject__create;
+    _ = @import("../../btjs.zig").dumpBtjsTrace;
    BunObject.exportAll();
 }

--- a/src/bun.js/bindings/CallFrame.zig
+++ b/src/bun.js/bindings/CallFrame.zig
@@ -190,4 +190,9 @@ pub const CallFrame = opaque {
            .column = column,
        };
    }
+
+    extern fn Bun__CallFrame__describeFrame(*const CallFrame) [*:0]const u8;
+    pub fn describeFrame(self: *const CallFrame) [:0]const u8 {
+        return std.mem.span(Bun__CallFrame__describeFrame(self));
+    }
 };
--- a/src/bun.js/bindings/bindings.cpp
+++ b/src/bun.js/bindings/bindings.cpp
@@ -6443,3 +6443,10 @@ CPP_DECL bool Bun__util__isInsideNodeModules(JSC::JSGlobalObject* globalObject,

    return inNodeModules;
 }
+
+#if BUN_DEBUG
+CPP_DECL const char* Bun__CallFrame__describeFrame(JSC::CallFrame* callFrame)
+{
+    return callFrame->describeFrame();
+}
+#endif
--- a/src/symbols.def
+++ b/src/symbols.def
@@ -572,6 +572,7 @@ EXPORTS
  node_api_create_property_key_latin1
  node_api_create_property_key_utf16
  node_api_create_property_key_utf8
+  dumpBtjsTrace
  ?TryGetCurrent@Isolate@v8@@SAPEAV12@XZ
  ?GetCurrent@Isolate@v8@@SAPEAV12@XZ
  ?GetCurrentContext@Isolate@v8@@QEAA?AV?$Local@VContext@v8@@@2@XZ
--- a/src/symbols.dyn
+++ b/src/symbols.dyn
@@ -224,4 +224,5 @@
    __ZN2v812api_internal17FromJustIsNothingEv;
    _uv_os_getpid;
    _uv_os_getppid;
+    _dumpBtjsTrace;
 };
--- a/src/symbols.txt
+++ b/src/symbols.txt
@@ -223,3 +223,4 @@ __ZNK2v85Value10IsFunctionEv
 __ZN2v812api_internal17FromJustIsNothingEv
 _uv_os_getpid
 _uv_os_getppid
+_dumpBtjsTrace