Fix segmentation fault during building stack traces string

src/bun.js/bindings/ZigStackFrame.zig

@@ -11,6 +11,9 @@ pub const ZigStackFrame = extern struct {
     /// This informs formatters whether to display as a blob URL or not
     remapped: bool = false,
 
+    /// -1 means not set.
+    jsc_stack_frame_index: i32 = -1,
+
     pub fn deinit(this: *ZigStackFrame) void {
         this.function_name.deref();
         this.source_url.deref();
@@ -213,6 +216,7 @@ pub const ZigStackFrame = extern struct {
         .source_url = .empty,
         .position = .invalid,
         .is_async = false,
+        .jsc_stack_frame_index = -1,
     };
 
     pub fn nameFormatter(this: *const ZigStackFrame, comptime enable_color: bool) NameFormatter {

src/bun.js/bindings/bindings.cpp

@@ -4772,25 +4772,37 @@ class V8StackTraceIterator {
 
 static void populateStackTrace(JSC::VM& vm, const WTF::Vector<JSC::StackFrame>& frames, ZigStackTrace& trace, JSC::JSGlobalObject* globalObject, PopulateStackTraceFlags flags)
 {
-    uint8_t frame_i = 0;
-    size_t stack_frame_i = 0;
-    const size_t total_frame_count = frames.size();
-    const uint8_t frame_count = total_frame_count < trace.frames_cap ? total_frame_count : trace.frames_cap;
-
-    while (frame_i < frame_count && stack_frame_i < total_frame_count) {
-        // Skip native frames
-        while (stack_frame_i < total_frame_count && !(frames.at(stack_frame_i).hasLineAndColumnInfo()) && !(frames.at(stack_frame_i).isWasmFrame())) {
+    if (flags == PopulateStackTraceFlags::OnlyPosition) {
+        uint8_t frame_i = 0;
+        size_t stack_frame_i = 0;
+        const size_t total_frame_count = frames.size();
+        const uint8_t frame_count = total_frame_count < trace.frames_cap ? total_frame_count : trace.frames_cap;
+
+        while (frame_i < frame_count && stack_frame_i < total_frame_count) {
+            // Skip native frames
+            while (stack_frame_i < total_frame_count && !(frames.at(stack_frame_i).hasLineAndColumnInfo()) && !(frames.at(stack_frame_i).isWasmFrame())) {
+                stack_frame_i++;
+            }
+            if (stack_frame_i >= total_frame_count)
+                break;
+
+            ZigStackFrame& frame = trace.frames_ptr[frame_i];
+            frame.jsc_stack_frame_index = static_cast<int32_t>(stack_frame_i);
+            populateStackFrame(vm, trace, frames[stack_frame_i], frame, frame_i == 0, &trace.referenced_source_provider, globalObject, flags);
             stack_frame_i++;
+            frame_i++;
+        }
+        trace.frames_len = frame_i;
+    } else if (flags == PopulateStackTraceFlags::OnlySourceLines) {
+        for (uint8_t i = 0; i < trace.frames_len; i++) {
+            ZigStackFrame& frame = trace.frames_ptr[i];
+            // A call with flags set to OnlySourceLines always follows a call with flags set to OnlyPosition,
+            // so jsc_stack_frame_index is always a valid value here.
+            ASSERT(frame.jsc_stack_frame_index >= 0);
+            ASSERT(static_cast<size_t>(frame.jsc_stack_frame_index) < frames.size());
+            populateStackFrame(vm, trace, frames[frame.jsc_stack_frame_index], frame, i == 0, &trace.referenced_source_provider, globalObject, flags);
         }
-        if (stack_frame_i >= total_frame_count)
-            break;
-
-        ZigStackFrame& frame = trace.frames_ptr[frame_i];
-        populateStackFrame(vm, trace, frames[stack_frame_i], frame, frame_i == 0, &trace.referenced_source_provider, globalObject, flags);
-        stack_frame_i++;
-        frame_i++;
     }
-    trace.frames_len = frame_i;
 }
 
 static JSC::JSValue getNonObservable(JSC::VM& vm, JSC::JSGlobalObject* global, JSC::JSObject* obj, const JSC::PropertyName& propertyName)

src/bun.js/bindings/headers-handwritten.h

@@ -183,6 +183,18 @@ typedef struct ZigStackFrame {
     ZigStackFrameCode code_type;
     bool is_async;
     bool remapped;
+    int32_t jsc_stack_frame_index;
+
+    ZigStackFrame()
+        : function_name {}
+        , source_url {}
+        , position {}
+        , code_type {}
+        , is_async(false)
+        , remapped(false)
+        , jsc_stack_frame_index(-1)
+    {
+    }
 } ZigStackFrame;
 
 typedef struct ZigStackTrace {

src/logger.zig

@@ -1335,15 +1335,6 @@ pub const Log = struct {
 
         if (needs_newline) _ = try to.write("\n");
     }
-
-    pub fn toZigException(this: *const Log, allocator: std.mem.Allocator) *js.ZigException.Holder {
-        var holder = try allocator.create(js.ZigException.Holder);
-        holder.* = js.ZigException.Holder.init();
-        var zig_exception: *js.ZigException = holder.zigException();
-        zig_exception.exception = this;
-        zig_exception.code = js.JSErrorCode.BundlerError;
-        return holder;
-    }
 };
 
 pub inline fn usize2Loc(loc: usize) Loc {
@@ -1617,7 +1608,6 @@ const Output = bun.Output;
 const StringBuilder = bun.StringBuilder;
 const assert = bun.assert;
 const default_allocator = bun.default_allocator;
-const js = bun.jsc;
 const jsc = bun.jsc;
 const strings = bun.strings;
 const Index = bun.ast.Index;