diff --git a/TeXmacs/tests/python/1294.py b/TeXmacs/tests/python/1294.py
new file mode 100755
index 0000000000..ba66d92e2e
--- /dev/null
+++ b/TeXmacs/tests/python/1294.py
@@ -0,0 +1,397 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""1294.py: 复现与验证 LaTeX 自递归宏粘贴崩溃的自动化测试脚本。
+
+支持用例:
+  - 1294_1.tex: 无参自递归宏 (用例 249)
+  - 1294_2.tex: 带参自递归宏 (用例 289)
+  - 1294_3.tex: 相互递归宏 (crash_pattern_c)
+
+启动命令: xmake r stem -d
+用法:
+  python3 TeXmacs/tests/python/1294.py               # 默认依序测试 1294_1.tex, 1294_2.tex, 1294_3.tex
+  python3 TeXmacs/tests/python/1294.py [path/to.tex] # 测试指定文件
+"""
+
+import os
+import sys
+import glob
+import time
+import subprocess
+import threading
+
+from Xlib import X, display, Xatom
+from Xlib.protocol import event
+from pynput.keyboard import Controller as Kbd, Key
+from pynput.mouse import Controller as Mouse, Button
+
+# 定位工程根目录
+_cur = os.path.dirname(os.path.abspath(__file__))
+while _cur and _cur != "/" and not os.path.isdir(os.path.join(_cur, "TeXmacs")):
+    _cur = os.path.dirname(_cur)
+ROOT_DIR = _cur if _cur else os.path.dirname(os.path.abspath(__file__))
+HERE = ROOT_DIR
+
+# 4K (3840x2312) 实测坐标
+POS_DOC = (960, 900)
+POS_EDIT_MENU = (220, 140)
+POS_PASTE_FROM = (227, 1008)
+POS_LATEX_ITEM = (618, 1135)
+
+DRAFT_DIRS = [
+    os.path.expanduser("~/文档/LiiiSTEM/no_name"),
+    os.path.expanduser("~/Documents/LiiiSTEM/no_name"),
+]
+
+DEFAULT_CASES = [
+    os.path.join(ROOT_DIR, "TeXmacs", "tests", "tex", "1294_1.tex"),
+    os.path.join(ROOT_DIR, "TeXmacs", "tests", "tex", "1294_2.tex"),
+    os.path.join(ROOT_DIR, "TeXmacs", "tests", "tex", "1294_3.tex"),
+]
+
+
+class X11Clipboard:
+    """X11 剪贴板持有者，在后台响应 SelectionRequest。"""
+
+    def __init__(self):
+        self.disp = display.Display()
+        self.screen = self.disp.screen()
+        self.window = self.screen.root.create_window(
+            0, 0, 1, 1, 0, self.screen.root_depth
+        )
+        self.CLIPBOARD = self.disp.intern_atom('CLIPBOARD')
+        self.PRIMARY = self.disp.intern_atom('PRIMARY')
+        self.TARGETS = self.disp.intern_atom('TARGETS')
+        self.UTF8 = self.disp.intern_atom('UTF8_STRING')
+        self.TEXT = self.disp.intern_atom('TEXT')
+        self.STRING = Xatom.STRING
+        self.text = ""
+        self.running = True
+        self.thread = threading.Thread(target=self._loop, daemon=True)
+        self.thread.start()
+
+    def set_text(self, text):
+        self.text = text
+        self.window.set_selection_owner(self.CLIPBOARD, X.CurrentTime)
+        self.window.set_selection_owner(self.PRIMARY, X.CurrentTime)
+        self.disp.flush()
+
+    def _loop(self):
+        while self.running:
+            try:
+                if self.disp.pending_events() == 0:
+                    time.sleep(0.01)
+                    continue
+                e = self.disp.next_event()
+                if e.type == X.SelectionRequest:
+                    req_win = self.disp.create_resource_object('window', e.requestor)
+                    prop = e.property
+                    if prop == X.NONE:
+                        prop = e.target
+                    if e.target == self.TARGETS:
+                        req_win.change_property(
+                            prop, Xatom.ATOM, 32,
+                            [self.TARGETS, self.UTF8, self.STRING, self.TEXT]
+                        )
+                        ev = event.SelectionNotify(
+                            time=e.time, requestor=e.requestor,
+                            selection=e.selection, target=e.target,
+                            property=prop
+                        )
+                    elif e.target in (self.UTF8, self.STRING, self.TEXT):
+                        req_win.change_property(
+                            prop, e.target, 8, self.text.encode('utf-8')
+                        )
+                        ev = event.SelectionNotify(
+                            time=e.time, requestor=e.requestor,
+                            selection=e.selection, target=e.target,
+                            property=prop
+                        )
+                    else:
+                        ev = event.SelectionNotify(
+                            time=e.time, requestor=e.requestor,
+                            selection=e.selection, target=e.target,
+                            property=X.NONE
+                        )
+                    req_win.send_event(ev)
+                    self.disp.flush()
+            except Exception:
+                pass
+
+    def stop(self):
+        self.running = False
+
+
+def clean_drafts():
+    """清理自动保存草稿，防止弹窗阻碍启动。"""
+    for d in DRAFT_DIRS:
+        if os.path.isdir(d):
+            for f in glob.glob(os.path.join(d, "draft_*.tmu")):
+                try:
+                    os.remove(f)
+                except OSError:
+                    pass
+
+
+def activate_window():
+    """激活 Mogan STEM 窗口。"""
+    js_code = (
+        'const wins = workspace.windowList ? workspace.windowList() : workspace.windows();\n'
+        'for (let i = 0; i < wins.length; i++) {\n'
+        '    const w = wins[i];\n'
+        '    const cls = (w.resourceClass || "").toLowerCase();\n'
+        '    const name = (w.resourceName || "").toLowerCase();\n'
+        '    const title = (w.caption || "");\n'
+        '    if (cls.includes("stem") || name.includes("stem") || title.includes("Mogan")) {\n'
+        '        workspace.activeWindow = w;\n'
+        '        if (w.activate) w.activate();\n'
+        '    }\n'
+        '}\n'
+    )
+    tmp_js = "/tmp/activate_moganstem.js"
+    with open(tmp_js, "w", encoding="utf-8") as f:
+        f.write(js_code)
+
+    try:
+        import dbus
+        bus = dbus.SessionBus()
+        kwin = bus.get_object("org.kde.KWin", "/Scripting")
+        iface = dbus.Interface(kwin, "org.kde.kwin.Scripting")
+        script_id = iface.loadScript(tmp_js)
+        script_obj = bus.get_object("org.kde.KWin", f"/Scripting/Script{script_id}")
+        script_iface = dbus.Interface(script_obj, "org.kde.kwin.Script")
+        script_iface.run()
+        iface.unloadScript(str(script_id))
+    except Exception:
+        pass
+
+    try:
+        d = display.Display()
+        root = d.screen().root
+        NET_ACTIVE_WINDOW = d.intern_atom('_NET_ACTIVE_WINDOW')
+        NET_CLIENT_LIST = d.intern_atom('_NET_CLIENT_LIST')
+        prop = root.get_full_property(NET_CLIENT_LIST, Xatom.WINDOW)
+        if prop:
+            for wid in prop.value:
+                win = d.create_resource_object('window', wid)
+                c = str(win.get_wm_class() or "").lower()
+                if "stem" in c or "mogan" in c:
+                    data = [2, X.CurrentTime, 0, 0, 0]
+                    ev = event.ClientMessage(window=wid, client_type=NET_ACTIVE_WINDOW, data=(32, data))
+                    root.send_event(ev, event_mask=X.SubstructureRedirectMask | X.SubstructureNotifyMask)
+                    d.flush()
+                    break
+    except Exception:
+        pass
+
+
+def is_window_ready():
+    try:
+        out = subprocess.check_output(
+            ["xprop", "-root", "_NET_CLIENT_LIST"],
+            text=True, stderr=subprocess.DEVNULL
+        )
+        for wid in out.split("#")[-1].replace(",", " ").split():
+            c = subprocess.check_output(
+                ["xprop", "-id", wid, "WM_CLASS"],
+                text=True, stderr=subprocess.DEVNULL
+            )
+            if "moganstem" in c.lower() or "liiistem" in c.lower():
+                return True
+    except Exception:
+        pass
+    return False
+
+
+class TestRunner:
+    def __init__(self):
+        self.proc = None
+        self.clip = X11Clipboard()
+        self.kbd = Kbd()
+        self.mouse = Mouse()
+
+    def start_app(self):
+        self.stop_app()
+        clean_drafts()
+        subprocess.run(["pkill", "-9", "-f", "moganstem"], stderr=subprocess.DEVNULL)
+
+        print("[1294] Starting Mogan STEM via: xmake r stem -d")
+        self.proc = subprocess.Popen(["xmake", "r", "stem", "-d"], cwd=HERE)
+
+        t0 = time.time()
+        while time.time() - t0 < 15:
+            if is_window_ready():
+                break
+            time.sleep(0.3)
+
+        time.sleep(1.0)
+        activate_window()
+        time.sleep(0.5)
+
+    def is_alive(self):
+        if self.proc is None:
+            return False
+        return self.proc.poll() is None
+
+    def stop_app(self):
+        if self.proc is not None:
+            if self.proc.poll() is None:
+                self.proc.terminate()
+                try:
+                    self.proc.wait(timeout=2)
+                except Exception:
+                    self.proc.kill()
+            self.proc = None
+        subprocess.run(["pkill", "-9", "-f", "moganstem"], stderr=subprocess.DEVNULL)
+        clean_drafts()
+
+    def run_case(self, case_name, tex_content):
+        """运行单个用例的粘贴测试。"""
+        if not self.is_alive():
+            self.start_app()
+
+        print(f"\n--- Running: {case_name} ---")
+        print(f"Content: {tex_content.strip()}")
+
+        # 新建标签页并聚焦
+        activate_window()
+        time.sleep(0.3)
+        self.kbd.press(Key.ctrl)
+        self.kbd.tap('t')
+        self.kbd.release(Key.ctrl)
+        time.sleep(0.8)
+
+        self.mouse.position = POS_DOC
+        time.sleep(0.2)
+        self.mouse.click(Button.left)
+        time.sleep(0.4)
+
+        # 设置剪贴板并粘贴
+        self.clip.set_text(tex_content)
+        activate_window()
+        time.sleep(0.2)
+
+        print("  -> Clicking: Edit -> Paste from -> LaTeX")
+        self.mouse.position = POS_EDIT_MENU
+        time.sleep(0.3)
+        self.mouse.click(Button.left)
+        time.sleep(0.4)
+
+        self.mouse.position = POS_PASTE_FROM
+        time.sleep(0.4)
+
+        self.mouse.position = POS_LATEX_ITEM
+        time.sleep(0.3)
+        self.mouse.click(Button.left)
+
+        # 检查粘贴阶段是否崩溃
+        t_wait = 0.0
+        crashed = False
+        while t_wait < 3.5:
+            time.sleep(0.2)
+            t_wait += 0.2
+            if not self.is_alive():
+                crashed = True
+                print("  [!] Crashed during paste!")
+                break
+
+        # 处理可能的错误弹窗并关闭
+        if not crashed:
+            time.sleep(0.5)
+            print("  -> Closing possible error popup (Enter)...")
+            self.kbd.tap(Key.enter)
+            time.sleep(0.5)
+            if not self.is_alive():
+                crashed = True
+                print("  [!] Crashed after dismissing popup!")
+
+        # 关闭弹窗后，继续编辑测试（防止损坏状态下继续操作引起崩溃）
+        if not crashed:
+            print("  -> Testing continue editing after paste...")
+            activate_window()
+            time.sleep(0.3)
+            self.mouse.position = POS_DOC
+            time.sleep(0.2)
+            self.mouse.click(Button.left)
+            time.sleep(0.3)
+
+            # 键入文本
+            self.kbd.type("testing edit after paste ")
+            time.sleep(0.3)
+            # 回车触发分段排版
+            self.kbd.tap(Key.enter)
+            time.sleep(0.3)
+            # 键入更多内容
+            self.kbd.type("continue typing 12345")
+            time.sleep(0.3)
+            # 回车
+            self.kbd.tap(Key.enter)
+            time.sleep(0.3)
+            # 退格删除
+            for _ in range(8):
+                self.kbd.tap(Key.backspace)
+                time.sleep(0.05)
+            # 光标移动
+            self.kbd.tap(Key.up)
+            time.sleep(0.1)
+            self.kbd.tap(Key.down)
+            time.sleep(0.1)
+            self.kbd.type(" finished")
+            time.sleep(0.5)
+
+            # 等待排版和可能的后台处理
+            t_wait = 0.0
+            while t_wait < 2.5:
+                time.sleep(0.2)
+                t_wait += 0.2
+                if not self.is_alive():
+                    crashed = True
+                    print("  [!] Crashed during continue editing!")
+                    break
+
+        status = "CRASH" if crashed else "PASS"
+        print(f"  Result for {case_name}: {status}")
+        return not crashed
+
+    def close(self):
+        self.clip.stop()
+        self.stop_app()
+
+
+def main():
+    if len(sys.argv) > 1:
+        test_files = sys.argv[1:]
+    else:
+        test_files = [f for f in DEFAULT_CASES if os.path.exists(f)]
+        if not test_files:
+            print("[!] Default test cases not found in TeXmacs/tests/tex/!")
+            sys.exit(1)
+
+    runner = TestRunner()
+    results = {}
+
+    try:
+        for tf in test_files:
+            name = os.path.basename(tf)
+            with open(tf, "r", encoding="utf-8") as f:
+                content = f.read().strip()
+            passed = runner.run_case(name, content)
+            results[name] = "PASS" if passed else "CRASH"
+
+        print("\n" + "=" * 50)
+        print("TEST SUMMARY:")
+        print("=" * 50)
+        all_passed = True
+        for name, status in results.items():
+            print(f"  {name:20s}: {status}")
+            if status != "PASS":
+                all_passed = False
+
+        sys.exit(0 if all_passed else 1)
+
+    finally:
+        runner.close()
+
+
+if __name__ == "__main__":
+    main()
diff --git a/TeXmacs/tests/tex/1294_1.tex b/TeXmacs/tests/tex/1294_1.tex
new file mode 100644
index 0000000000..d1762fe4d3
--- /dev/null
+++ b/TeXmacs/tests/tex/1294_1.tex
@@ -0,0 +1 @@
+\def\crashMacro24{\crashMacro24} \crashMacro24 % 自递归宏定义，触发粘贴 LaTeX 崩溃 (用例 249, devel/1294.md)
diff --git a/TeXmacs/tests/tex/1294_2.tex b/TeXmacs/tests/tex/1294_2.tex
new file mode 100644
index 0000000000..e98c96d8ba
--- /dev/null
+++ b/TeXmacs/tests/tex/1294_2.tex
@@ -0,0 +1 @@
+\def\paramRec28#1{\paramRec28{#1}#1} \paramRec28{x} % 带参递归 (用例 289, devel/1294.md)
diff --git a/TeXmacs/tests/tex/1294_3.tex b/TeXmacs/tests/tex/1294_3.tex
new file mode 100644
index 0000000000..ffc345a2b9
--- /dev/null
+++ b/TeXmacs/tests/tex/1294_3.tex
@@ -0,0 +1,3 @@
+\newcommand{\macroA}{\macroB}
+\newcommand{\macroB}{\macroA}
+\macroA
diff --git a/devel/1294.md b/devel/1294.md
new file mode 100644
index 0000000000..6b0c61fbe8
--- /dev/null
+++ b/devel/1294.md
@@ -0,0 +1,106 @@
+# 1294 LaTeX 崩溃用例修复（latex_crash_1）
+
+## 背景
+
+崩溃用例集（`/home/da/git/crash/`）中的用例 249：
+
+```latex
+\def\crashMacro24{\crashMacro24} \crashMacro24
+```
+
+在 GUI 中执行「编辑 → 粘贴自 → LaTeX」后约 2.6 秒进程崩溃退出（用户现场 SIGSEGV，
+本地 C++ 测试环境下表现为未捕获异常导致进程终止，退出码 255）。
+
+## What
+
+- 新增 C++ 回归测试 `tests/Plugins/Tex/parsetex_test.cpp`（包含用例 249、289 与 pattern_c）。
+- 新增自动化 GUI 回归测试脚本 `TeXmacs/tests/python/1294.py`。
+- 落实「排版引擎」+「LaTeX 转换」双层防御：
+  1. 排版引擎层：`concater_rep::typeset_compound` 与 `typeset_auto` 增加宏展开深度限制，超限降级为占位 box，防止任何宏递归引起栈溢出崩溃。
+  2. LaTeX 转换层：`has_macro_cycle` 环路检测，识别自递归或相互递归宏定义并降级返回空，避免向用户文档插入需要手动删除的损坏内容。
+
+## Why（根因定位过程）
+
+用例 249（`\def\crashMacro24{\crashMacro24} \crashMacro24`）与用例 289（`\def\paramRec28#1{\paramRec28{#1}#1} \paramRec28{x}`）
+在通过「编辑 → 粘贴自 → LaTeX」粘贴入文档后触发崩溃，通过 addr2line 与 coredump 定位真实根因：
+
+1. **LaTeX 转换层面**：
+   `\def\crashMacro24{...}` 会被正常解析为 `<assign|crashMacro|<macro|<crashMacro>24>>`，
+   属于带有自引用环路的宏定义。
+2. **排版引擎层面**：
+   在文档被插入或用户按回车排版时，排版引擎进入 `concater_rep::typeset_compound`。
+   展开宏体后再次遇到宏调用，形成递归环路：
+   `typeset_compound` (concat_macro.cpp) → `typeset` (concater.cpp) → `typeset_concat` (concat_text.cpp) → `typeset` → `typeset_compound`。
+   无展开深度上限，导致调用栈超过 47,000+ 帧直至栈溢出（SIGSEGV）。
+
+## How
+
+- `src/Typeset/env.hpp` & `src/Typeset/Env/env.cpp`：
+  在 `edit_env` 中增加 `macro_depth` 深度计数。
+- `src/Typeset/Concat/concat_macro.cpp`：
+  引入 RAII 深度保护器 `macro_depth_guard`，在 `concater_rep::typeset_compound` 与
+  `concater_rep::typeset_auto` 中限制展开深度（上限 100）。超限时输出警告并降级渲染
+  占位 box，杜绝无限递归死循环与爆栈。
+- `src/Plugins/Tex/fromtex_post.cpp`：
+  新增 `has_macro_cycle` 依赖图环路检测算法。在 `latex_to_tree` 入口对转换后的树
+  进行宏定义成环校验；检测到自递归或相互递归宏时记录警告并降级返回空，确保
+  损坏的递归宏不会被粘贴进用户文档。
+- `src/Graphics/Fonts/find_font.cpp`：
+  `find_font (tree)` 增加静态递归深度计数，规则成环时按"字体未找到"降级返回 nil font。
+
+## 涉及文件
+
+- `devel/1294.md`（任务文档）
+- `src/Typeset/env.hpp`
+- `src/Typeset/Env/env.cpp`
+- `src/Typeset/Concat/concat_macro.cpp`
+- `src/Plugins/Tex/fromtex_post.cpp`
+- `src/Graphics/Fonts/find_font.cpp`
+- `tests/Plugins/Tex/parsetex_test.cpp`（回归测试，含 249、289 与 1294_3 用例）
+- `TeXmacs/tests/tex/1294_1.tex`（用例 249 样本）
+- `TeXmacs/tests/tex/1294_2.tex`（用例 289 样本）
+- `TeXmacs/tests/tex/1294_3.tex`（用例 crash_pattern_c 相互递归样本）
+- `TeXmacs/tests/python/1294.py`（自动化 GUI 粘贴回归测试脚本）
+
+## 测试
+
+```bash
+# 1. C++ 单元与回归测试
+xmake b parsetex_test && xmake r parsetex_test
+xmake r 0620
+xmake r 0631
+
+# 2. GUI 自动化测试（使用 pynput 驱动真实 GUI）
+python3 TeXmacs/tests/python/1294.py
+# 预期：1294_1.tex、1294_2.tex 和 1294_3.tex 均 PASS，
+# 覆盖完整流程：粘贴 -> 关闭错误弹窗 -> 继续键入/分段/删除/光标移动编辑 -> 进程均不崩溃退出
+```
+
+### 手动测试方法
+
+1. 构建并启动 Mogan STEM：`xmake r stem`；
+2. 用文本编辑器打开仓库中的 `TeXmacs/tests/tex/1294_1.tex`，全选并复制文件全部内容；
+3. 在 Mogan STEM 中新建一个空白文档；
+4. 点击菜单「编辑 → 粘贴自 → LaTeX」；
+5. 预期：
+   - 修复前：粘贴后约 2.6 秒进程闪退（SIGSEGV）；
+   - 修复后：粘贴正常完成，进程不退出、不闪退。
+
+0628 / 0190 存量失败（导出方向 / scheme lazy-define），已用未含修复的基线构建复验，
+与本任务改动无关。
+
+## 备注
+
+- 粘贴完整链路：`clipboard-paste-import "latex"` → `selection_paste`（C++）→
+  `generic_to_tree (s, "latex-snippet")` → scheme `convert` → `parse-latex`（C++
+  `parse_latex`）→ `latex->texmacs`（C++ `latex_to_tree`）。
+- GUI 手动验证（含崩溃用例 249 现象消失）由用户执行。
+
+## 迭代改进记录
+
+- 针对 `dfd860e0f` 中精简 `tree_calls_macro` 时误删 `L(t)` 与 `COMPOUND`/`APPLY` 匹配导致 `has_macro_cycle` 漏判宏环路的问题进行了修复：
+  - `src/Plugins/Tex/fromtex_post.cpp`：恢复 `L(t)` 比较与 `COMPOUND`/`APPLY` 运算符提取，准确识别宏复合节点。
+  - `src/Plugins/Tex/tex.hpp`：导出 `bool has_macro_cycle (tree t)` 接口。
+  - `tests/Plugins/Tex/parsetex_test.cpp`：新增 `test_has_macro_cycle` 独立断言用例，覆盖自递归、带参自递归、相互递归与正常宏，杜绝漏检回归。
+  - `TeXmacs/tests/python/1294.py`：明确采用 `pynput` 完善全流程自动化测试，在粘贴后主动关闭可能的错误弹窗，并模拟用户在文档中继续输入文本、回车分段排版、退格删除以及光标移动等连续编辑操作，验证全过程均不 crash。
+
diff --git a/src/Graphics/Fonts/find_font.cpp b/src/Graphics/Fonts/find_font.cpp
index 4e01acb20c..60e869fd9a 100644
--- a/src/Graphics/Fonts/find_font.cpp
+++ b/src/Graphics/Fonts/find_font.cpp
@@ -198,12 +198,29 @@ find_font_bis (tree t) {
   return font ();
 }
 
+// 析构时回退递归计数并结算计时，异常路径（底层字体加载抛异常）同样生效
+struct find_font_guard {
+  int& level;
+  find_font_guard (int& l) : level (l) { level++; }
+  ~find_font_guard () {
+    level--;
+    bench_cumul ("find font");
+  }
+};
+
 font
 find_font (tree t) {
+  static int find_font_level= 0;
+  // 规则驱动的递归转换缺乏终止保证，字体规则成环时会无限递归直到栈溢出，
+  // 这里限制递归深度，超限按"字体未找到"降级
+  static const int max_find_font_level= 100;
+  if (find_font_level >= max_find_font_level) {
+    failed_error << "find_font recursion too deep, giving up on " << t << "\n";
+    return font ();
+  }
   bench_start ("find font");
-  font fn= find_font_bis (t);
-  bench_cumul ("find font");
-  return fn;
+  find_font_guard guard (find_font_level);
+  return find_font_bis (t);
 }
 
 font
diff --git a/src/Plugins/Tex/fromtex_post.cpp b/src/Plugins/Tex/fromtex_post.cpp
index 774c2a70af..b28f0eb927 100644
--- a/src/Plugins/Tex/fromtex_post.cpp
+++ b/src/Plugins/Tex/fromtex_post.cpp
@@ -2443,8 +2443,8 @@ guess_missing (tree t) {
  * Interface
  ******************************************************************************/
 
-tree
-latex_to_tree (tree t0) {
+static tree
+latex_to_tree_body (tree t0) {
   // cout << "\n\nt0= " << t0 << "\n\n";
   tree   t1= kill_space_invaders (t0);
   string style, lan= "";
@@ -2539,6 +2539,93 @@ latex_to_tree (tree t0) {
   else return t15;
 }
 
+static bool
+tree_calls_macro (tree t, string name) {
+  if (is_atomic (t)) return t->label == name;
+  string l= as_string (L (t));
+  if (l == name) return true;
+  if (is_func (t, COMPOUND) && N (t) > 0 && is_atomic (t[0]) &&
+      t[0]->label == name)
+    return true;
+  if (is_func (t, APPLY) && N (t) > 0 && is_atomic (t[0]) &&
+      t[0]->label == name)
+    return true;
+  for (int i= 0; i < N (t); i++)
+    if (tree_calls_macro (t[i], name)) return true;
+  return false;
+}
+
+static void
+find_macro_definitions (tree t, array<string>& names, array<tree>& bodies) {
+  if (is_atomic (t)) return;
+  if (is_func (t, ASSIGN, 2)) {
+    tree   var = t[0];
+    tree   val = t[1];
+    string name= is_atomic (var) ? var->label : as_string (var);
+    if (N (name) > 0 && !is_atomic (val)) {
+      names << name;
+      bodies << val;
+    }
+  }
+  for (int i= 0; i < N (t); i++)
+    find_macro_definitions (t[i], names, bodies);
+}
+
+static bool
+dfs_macro_cycle (int u, const array<array<int>>& adj, array<int>& state) {
+  state[u]= 1;
+  for (int k= 0; k < N (adj[u]); k++) {
+    int v= adj[u][k];
+    if (state[v] == 1) return true;
+    if (state[v] == 0 && dfs_macro_cycle (v, adj, state)) return true;
+  }
+  state[u]= 2;
+  return false;
+}
+
+bool
+has_macro_cycle (tree t) {
+  array<string> names;
+  array<tree>   bodies;
+  find_macro_definitions (t, names, bodies);
+  int n= N (names);
+  if (n == 0) return false;
+
+  array<array<int>> adj (n);
+  for (int i= 0; i < n; i++) {
+    adj[i]= array<int> ();
+    for (int j= 0; j < n; j++)
+      if (tree_calls_macro (bodies[i], names[j])) adj[i] << j;
+  }
+
+  array<int> state (n);
+  for (int i= 0; i < n; i++)
+    state[i]= 0;
+  for (int i= 0; i < n; i++)
+    if (state[i] == 0 && dfs_macro_cycle (i, adj, state)) return true;
+  return false;
+}
+
+tree
+latex_to_tree (tree t0) {
+  // 转换过程中会触发样式环境求值与字体解析，环境缺字体时底层以异常上报
+  // （TM_FAILED 抛 string），异常穿过 scheme 边界会直接终止进程，
+  // 因此在转换入口兜底，降级为空文档。
+  // 同时检测自递归/循环宏定义，存在环路时直接降级返回空，避免向文档插入死循环内容。
+  try {
+    tree r= latex_to_tree_body (t0);
+    if (has_macro_cycle (r)) {
+      failed_error << "latex_to_tree: recursive macro definition detected, "
+                      "returning empty\n";
+      return tree (DOCUMENT, "");
+    }
+    return r;
+  } catch (string msg) {
+    failed_error << "latex_to_tree failure: " << msg << "\n";
+    return tree (DOCUMENT, "");
+  }
+}
+
 tree
 latex_document_to_tree (string s, bool as_pic) {
   tree r;
diff --git a/src/Plugins/Tex/tex.hpp b/src/Plugins/Tex/tex.hpp
index 59dd3c22ec..fcd5f75dd3 100644
--- a/src/Plugins/Tex/tex.hpp
+++ b/src/Plugins/Tex/tex.hpp
@@ -21,6 +21,7 @@ tree   parse_latex_document (string s, bool change= false, bool as_pic= false);
 tree   latex_to_tree (tree t);
 tree   latex_document_to_tree (string s, bool as_pic= false);
 tree   latex_class_document_to_tree (string s);
+bool   has_macro_cycle (tree t);
 string latex_verbarg_to_string (tree t);
 string get_latex_style (tree t);
 string string_arg (tree t, bool u= false);
diff --git a/src/Typeset/Concat/concat_macro.cpp b/src/Typeset/Concat/concat_macro.cpp
index 06d7ccbfaf..b1c4d4a6ae 100644
--- a/src/Typeset/Concat/concat_macro.cpp
+++ b/src/Typeset/Concat/concat_macro.cpp
@@ -11,6 +11,7 @@
 
 #include "concater.hpp"
 #include "observers.hpp"
+#include "tm_debug.hpp"
 #include "tm_url.hpp"
 
 using namespace moebius;
@@ -93,10 +94,30 @@ concater_rep::typeset_with (tree t, path ip) {
   STACK_DELETE_ARRAY (newv);
 }
 
+// \def\a{\a} 之类的自递归宏在宏展开处无限递归直至栈溢出，
+// 限制宏展开嵌套深度，超限按占位标记降级渲染
+static const int max_macro_depth= 100;
+
+struct macro_depth_guard {
+  int& depth;
+  macro_depth_guard (int& d) : depth (d) { depth++; }
+  ~macro_depth_guard () { depth--; }
+};
+
+bool
+concater_rep::macro_depth_exceeded (tree t, path ip) {
+  if (env->macro_depth < max_macro_depth) return false;
+  failed_error << "macro expansion too deep: " << as_string (L (t)) << "\n";
+  print (test_box (ip));
+  return true;
+}
+
 void
 concater_rep::typeset_compound (tree t, path ip) {
-  int  d;
-  tree f;
+  if (macro_depth_exceeded (t, ip)) return;
+  macro_depth_guard guard (env->macro_depth);
+  int               d;
+  tree              f;
   if (L (t) == COMPOUND) {
     if (N (t) == 0) {
       typeset_error (t, ip);
@@ -168,6 +189,8 @@ concater_rep::typeset_compound (tree t, path ip) {
 
 void
 concater_rep::typeset_auto (tree t, path ip, tree f) {
+  if (macro_depth_exceeded (t, ip)) return;
+  macro_depth_guard guard (env->macro_depth);
   env->macro_arg= list<hashmap<string, tree>> (hashmap<string, tree> (UNINIT),
                                                env->macro_arg);
   env->macro_src= list<hashmap<string, path>> (
diff --git a/src/Typeset/Concat/concater.hpp b/src/Typeset/Concat/concater.hpp
index 9bc9abd44c..eedfc9e915 100644
--- a/src/Typeset/Concat/concater.hpp
+++ b/src/Typeset/Concat/concater.hpp
@@ -107,6 +107,7 @@ class concater_rep {
   void typeset_error (tree t, path ip);
 
   // active macro mechanisms
+  bool macro_depth_exceeded (tree t, path ip);
   void typeset_assign (tree t, path ip);
   void typeset_provide (tree t, path ip);
   void typeset_with (tree t, path ip);
diff --git a/src/Typeset/Env/env.cpp b/src/Typeset/Env/env.cpp
index a6f47860d6..d7cdebcb01 100644
--- a/src/Typeset/Env/env.cpp
+++ b/src/Typeset/Env/env.cpp
@@ -48,6 +48,7 @@ edit_env_rep::edit_env_rep (drd_info& drd2, url base_file_name2,
   complete   = false;
   recover_env= tuple ();
   anim_start= anim_end= anim_portion= 0.0;
+  macro_depth                       = 0;
 }
 
 edit_env::edit_env (drd_info& drd, url base_file_name,
diff --git a/src/Typeset/env.hpp b/src/Typeset/env.hpp
index 0229433eec..42f4d81a4b 100644
--- a/src/Typeset/env.hpp
+++ b/src/Typeset/env.hpp
@@ -189,6 +189,7 @@ class edit_env_rep : public concrete_struct {
   int      spacing_policy;
   tree     math_font_sizes;
   int      nesting_level;
+  int      macro_depth;
 
   int    info_level;
   int    src_style;
diff --git a/tests/Plugins/Tex/parsetex_test.cpp b/tests/Plugins/Tex/parsetex_test.cpp
new file mode 100644
index 0000000000..d19b1ff0ac
--- /dev/null
+++ b/tests/Plugins/Tex/parsetex_test.cpp
@@ -0,0 +1,116 @@
+/******************************************************************************
+ * MODULE     : parsetex_test.cpp
+ * DESCRIPTION: Tests for latex parser
+ * COPYRIGHT  : (C) 2026 Darcy Shen
+ *******************************************************************************
+ * This software falls under the GNU general public license version 3 or later.
+ * It comes WITHOUT ANY WARRANTY WHATSOEVER. For details, see the file LICENSE
+ * in the root directory or <http://www.gnu.org/licenses/gpl-3.0.html>.
+ ******************************************************************************/
+
+#include <QtTest/QtTest>
+
+#include "Tex/tex.hpp"
+#include "base.hpp"
+#include "boot.hpp"
+#include "file.hpp"
+#include "server.hpp"
+#include "tm_sys_utils.hpp"
+#include <s7_tm.hpp>
+
+extern s7_pointer user_env;
+
+class TestParseTex : public QObject {
+  Q_OBJECT
+
+private:
+  server* sv;
+  // latex_document_to_tree 是粘贴路径的完整转换入口；
+  // 复现代码与手动测试共用 TeXmacs/tests/tex/ 下的样本
+  void check_crash_case (const char* file);
+
+private slots:
+  void initTestCase ();
+  void test_crash_case_249 ();
+  void test_crash_case_289 ();
+  void test_crash_case_1294_3 ();
+  void test_has_macro_cycle ();
+};
+
+void
+TestParseTex::initTestCase () {
+  init_lolly ();
+  init_texmacs_home_path ();
+  init_texmacs_front ();
+  int   argc  = 1;
+  char* argv[]= {(char*) "parsetex_test", nullptr};
+  gui_open (argc, argv);
+  if (!tm_s7) {
+    tm_s7   = s7_init ();
+    user_env= s7_inlet (tm_s7, s7_nil (tm_s7));
+    s7_gc_protect (tm_s7, user_env);
+  }
+  sv= new server (app_type::RESEARCH);
+}
+
+void
+TestParseTex::check_crash_case (const char* file) {
+  string s;
+  QVERIFY2 (!load_string (url_system (string ("$TEXMACS_PATH/tests/tex/") *
+                                      string (file)),
+                          s, true),
+            "cannot load crash case tex file");
+  tree doc= latex_document_to_tree (s);
+  QVERIFY (is_func (doc, moebius::DOCUMENT));
+}
+
+void
+TestParseTex::test_crash_case_249 () {
+  // 无参自递归宏定义
+  check_crash_case ("1294_1.tex");
+}
+
+void
+TestParseTex::test_crash_case_289 () {
+  // 带参自递归宏定义
+  check_crash_case ("1294_2.tex");
+}
+
+void
+TestParseTex::test_crash_case_1294_3 () {
+  // 相互递归宏定义 (crash_pattern_c)
+  check_crash_case ("1294_3.tex");
+}
+
+void
+TestParseTex::test_has_macro_cycle () {
+  // 1. 无参自递归: \def\foo{\foo} -> <assign|foo|<macro|<foo>>>
+  tree self_rec=
+      tuple (compound ("assign", "foo", compound ("macro", compound ("foo"))));
+  QVERIFY (has_macro_cycle (self_rec));
+
+  // 2. 带参自递归: \def\foo#1{\foo{#1}} -> <assign|foo|<macro|x|<foo|<arg|x>>>>
+  tree param_rec= tuple (compound (
+      "assign", "foo",
+      compound ("macro", "x", compound ("foo", compound ("arg", "x")))));
+  QVERIFY (has_macro_cycle (param_rec));
+
+  // 3. 相互递归: foo 调 bar, bar 调 foo
+  tree mutual_rec=
+      tuple (compound ("assign", "foo", compound ("macro", compound ("bar"))),
+             compound ("assign", "bar", compound ("macro", compound ("foo"))));
+  QVERIFY (has_macro_cycle (mutual_rec));
+
+  // 4. 非递归正常宏: foo 调内置命令，无环
+  tree normal_macro= tuple (compound (
+      "assign", "foo",
+      compound ("macro", "x", compound ("bold", compound ("arg", "x")))));
+  QVERIFY (!has_macro_cycle (normal_macro));
+
+  // 5. 普通文档无宏定义
+  tree no_macro= compound ("document", "Hello world");
+  QVERIFY (!has_macro_cycle (no_macro));
+}
+
+QTEST_MAIN (TestParseTex)
+#include "parsetex_test.moc"