0.19.1 --- a name beneath a volume is absolute, and openkal-musl is a compatible range

README.md

@@ -6,7 +6,7 @@ C library.
 
 ```toml
 [dependencies]
-openkal-llvm-runtime = "0.19.0"
+openkal-llvm-runtime = "0.19.1"
 ```
 
 > **Engine floor (mcpp 2026.11.2.1):** 0.17.0 is built over openkal-musl 0.26.0,
@@ -330,6 +330,15 @@ grants against raw file truncation. The runtime implementation is unchanged.
 
 ## OpenKal 0.24 dependency group
 
+Runtime 0.19.1 reads a name beneath a volume, `X:/...`, as the C library beneath
+does: `X:` is the root name and `/` the root directory, so the working directory on
+a system with volumes is absolute and `absolute`, `canonical` and `relative` keep
+it (openkal-llvm-runtime#64). `X:` without a separator stays an ordinary name.
+Both probes (`examples/cxx`, `examples/image-cxx`) state the decomposition, the
+append and the working-directory results; without the change four of them fail on
+Linux and the working-directory results fail on Windows. The dependency on
+openkal-musl is the compatible range `^0.28.0`.
+
 Runtime 0.19.0 selects openkal-musl 0.28.0 and its matching OpenKal 0.24
 implementations. The C++ runtime surface and allocator feature selection
 remain unchanged.

examples/cxx/src/main.cpp

@@ -129,6 +129,32 @@ int main() {
         check(same, "a string grows past the allocator's own mappings");
     }
 
+    // --- names beneath a volume (openkal-llvm-runtime#64) -------------------
+    //
+    // The C library names a file on a system with volumes `D:/...` and takes
+    // `X:/` as a root. The same name is absolute to std::filesystem, and the
+    // working directory is absolute on every system.
+    {
+        namespace fs = std::filesystem;
+        const fs::path v = "D:/a/b.txt";
+        check(v.is_absolute() && v.root_name() == "D:" && v.root_directory() == "/", "`D:/a/b.txt' has a root name and a root directory");
+        check(v.relative_path() == "a/b.txt" && v.parent_path() == "D:/a" && v.filename() == "b.txt", "and decomposes beneath it");
+        std::vector<std::string> forward, backward;
+        for (const auto& e : v) forward.push_back(e.string());
+        for (auto it = v.end(); it != v.begin();) backward.insert(backward.begin(), (--it)->string());
+        check(forward == std::vector<std::string>{"D:", "/", "a", "b.txt"} && backward == forward, "its elements are the same read either way");
+        check(!fs::path("D:").is_absolute() && fs::path("D:").root_name().empty(), "`D:' without a separator is an ordinary name");
+        check(!fs::path("D:x").is_absolute(), "`D:x' is relative");
+        check((fs::path("x") / "D:/y") == "D:/y" && fs::path("x").append(std::string("D:/y")) == "D:/y", "appending an absolute volume name replaces the path");
+        check(fs::path("D:/a/b").lexically_relative("D:/a") == "b" && fs::path("/a/b").is_absolute(), "a name relative to a volume, and `/' unchanged");
+        std::error_code cwd_ec;
+        const fs::path cwd = fs::current_path(cwd_ec);
+        check(!cwd_ec && cwd.is_absolute(), "the working directory is absolute");
+        check(fs::absolute(cwd, cwd_ec) == cwd && !cwd_ec, "absolute() of it is itself");
+        const fs::path can = fs::canonical(cwd, cwd_ec);
+        check(!cwd_ec && can.is_absolute(), "canonical() of it succeeds");
+    }
+
     // --- std::filesystem, which is the C++ face of openkal.fs ---------------
 
     namespace fs = std::filesystem;

examples/image-cxx/src/main.cpp

@@ -39,6 +39,32 @@ int main(int argc, char** argv) {
 
     check(std::format("{:>6.2f}", 3.14159) == "  3.14", "formatting a floating-point value");
 
+    // --- names beneath a volume (openkal-llvm-runtime#64) -------------------
+    //
+    // The C library names a file on a system with volumes `D:/...` and takes
+    // `X:/` as a root. The same name is absolute to std::filesystem, and the
+    // working directory is absolute on every system.
+    {
+        namespace fs = std::filesystem;
+        const fs::path v = "D:/a/b.txt";
+        check(v.is_absolute() && v.root_name() == "D:" && v.root_directory() == "/", "`D:/a/b.txt' has a root name and a root directory");
+        check(v.relative_path() == "a/b.txt" && v.parent_path() == "D:/a" && v.filename() == "b.txt", "and decomposes beneath it");
+        std::vector<std::string> forward, backward;
+        for (const auto& e : v) forward.push_back(e.string());
+        for (auto it = v.end(); it != v.begin();) backward.insert(backward.begin(), (--it)->string());
+        check(forward == std::vector<std::string>{"D:", "/", "a", "b.txt"} && backward == forward, "its elements are the same read either way");
+        check(!fs::path("D:").is_absolute() && fs::path("D:").root_name().empty(), "`D:' without a separator is an ordinary name");
+        check(!fs::path("D:x").is_absolute(), "`D:x' is relative");
+        check((fs::path("x") / "D:/y") == "D:/y" && fs::path("x").append(std::string("D:/y")) == "D:/y", "appending an absolute volume name replaces the path");
+        check(fs::path("D:/a/b").lexically_relative("D:/a") == "b" && fs::path("/a/b").is_absolute(), "a name relative to a volume, and `/' unchanged");
+        std::error_code cwd_ec;
+        const fs::path cwd = fs::current_path(cwd_ec);
+        check(!cwd_ec && cwd.is_absolute(), "the working directory is absolute");
+        check(fs::absolute(cwd, cwd_ec) == cwd && !cwd_ec, "absolute() of it is itself");
+        const fs::path can = fs::canonical(cwd, cwd_ec);
+        check(!cwd_ec && can.is_absolute(), "canonical() of it succeeds");
+    }
+
     std::println("-- failures: {} --", failures);
     return failures ? 1 : 0;
 }

llvm/PATCHES.md

@@ -29,10 +29,10 @@ grep -rn "openkal ─── BEGIN" llvm/
 
 ## 已替换
 
- 五处,四个文件,一个判据 —— 每一处都能填进上面那句话。
+ 六处,五个文件,一个判据 —— 每一处都能填进上面那句话。
 
 ```sh
-grep -rn "openkal ─── BEGIN" llvm/    # 10 处标记(含配对的 #else/#endif)
+grep -rn "openkal ─── BEGIN" llvm/    # 30 处 BEGIN 标记
 ```
 
 | 文件 | 上游按什么分派 | 平台面 | openkal 的答案 |
@@ -42,6 +42,21 @@ grep -rn "openkal ─── BEGIN" llvm/    # 10 处标记(含配对的 #else/#e
 | `libunwind/src/RWMutex.hpp` | `_WIN32` | 读写锁 | pthread ⇒ musl ⇒ `kal_task_*` |
 | `libunwind/src/UnwindCursor.hpp` | `_WIN32` | (无) | 整段没被用到,只是被 include |
 | `compiler-rt/…/emutls.c` | `_WIN32` | 互斥 + 对齐分配 | pthread + `posix_memalign` |
+| `libcxx/src/filesystem/path_parser.h` | `_LIBCPP_WIN32API` | 名字的根 | C 库的根：`/` 与 `X:/`（0.19.1） |
+
+### `libcxx/src/filesystem/path_parser.h` 与 `port/include/__filesystem/path.h` — 卷下的名字（0.19.1）
+
+C 库（openkal-musl）在有卷的系统上把文件写作 `D:/...`，并像对待 `/` 一样把 `X:/` 当作根
+（其 `root_length`）。libc++ 只在 `_LIBCPP_WIN32API` 下识别盘符，按 POSIX 规则读 `D:/a` 时它是
+相对名：工作目录的 `is_absolute()` 为假，`absolute`、`canonical`、`relative` 拼出不存在的名字
+（openkal-llvm-runtime#64）。
+
+- `path_parser.h` 的 `consumeRootName` 在 `OPENKAL` 下接受后面紧跟 `/` 的 `X:` 作为根名，正向与
+  反向解析都一样；不带分隔符的 `X:` 仍是普通名字，与 C 库一致。`path_parser.h` 由同目录的
+  `.cpp` 以引号包含，无法遮蔽，所以原地标记。
+- `__filesystem/path.h` 的 `append(Source)` 在 POSIX 分支只看首字符是否为分隔符；覆盖件在
+  `OPENKAL` 或 `__OPENKAL__` 下改用 `path::is_absolute()` 判断，使 `path / "D:/y"` 与
+  `path / path("D:/y")` 结果相同。头文件按本文的约定放在 `port/include/` 覆盖，vendored 树不动。
 
 ### `libcxx/src/atomic.cpp` — `std::atomic` 的等待与唤醒
 

llvm/libcxx/src/filesystem/path_parser.h

@@ -329,6 +329,27 @@ struct PathParser {
       return Ret;
     if (PosPtr Ret = consumeNetworkRoot(P, End))
       return Ret;
+// ─── openkal ─── BEGIN ────────────────────────────────────────────────────────
+#elif defined(OPENKAL)
+    // openkal: A VOLUME IS A ROOT NAME WHEN A SEPARATOR FOLLOWS IT.
+    //
+    // The C library beneath (openkal-musl) names a file on a system with
+    // volumes `D:/...`, and takes `X:/` as a root exactly as it takes `/`
+    // (its root_length). Read as a POSIX name, `D:/a` was relative, so
+    // `current_path().is_absolute()` was false and `absolute`, `canonical`
+    // and `relative` built names that do not exist (openkal-llvm-runtime#64).
+    // `D:` without a separator stays an ordinary name, as it is to the C
+    // library.
+    if (P < End) {
+      if (End - P >= 3 && isDriveLetter(P[0]) && P[1] == ':' && P[2] == '/')
+        return P + 2;
+    } else if (P != End) {
+      const PosPtr First = Path.data();
+      const PosPtr Last  = Path.data() + Path.size();
+      if (P - 1 == First && P - 1 > End && P[0] == ':' && isDriveLetter(P[-1]) && P + 1 < Last && P[1] == '/')
+        return P - 2;
+    }
+// ─── openkal ─── END ──────────────────────────────────────────────────────────
 #endif
     return nullptr;
   }

mcpp.toml

@@ -1,7 +1,7 @@
 [package]
 namespace   = "mcpplibs"
 name        = "openkal-llvm-runtime"
-version     = "0.19.0"
+version     = "0.19.1"
 description = "LLVM's C++ runtime libraries — libc++, libc++abi and libunwind — configured for openkal-musl rather than for a host C library."
 license     = "Apache-2.0"
 authors     = ["mcpplibs"]
@@ -230,10 +230,10 @@ cflags = ["-DDISABLE_AARCH64_FMV=1"]
 # (measured on OpenSBI: every request for an arena refused, ENOMEM). A
 # target's edge replaces a general one, so each states every feature.
 [target.'cfg(not(os = "none"))'.dependencies]
-openkal-musl = { version = "0.28.0", default-features = false, features = ["posix", "malloc-mimalloc"] }
+openkal-musl = { version = "^0.28.0", default-features = false, features = ["posix", "malloc-mimalloc"] }
 
 [target.'cfg(os = "none")'.dependencies]
-openkal-musl = { version = "0.28.0", default-features = false, features = ["posix", "malloc-mallocng"] }
+openkal-musl = { version = "^0.28.0", default-features = false, features = ["posix", "malloc-mallocng"] }
 
 [build]