Windows support (wip): target layer, Microsoft x64 ABI, portable runtime, CI

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/target.cpp

@@ -0,0 +1,112 @@
+#include "target.h"
+
+#include <llvm/TargetParser/Host.h>
+
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+#ifdef _WIN32
+#define popen _popen
+#define pclose _pclose
+#else
+#include <sys/wait.h>
+#endif
+
+static bool hostIsWindows() {
+#ifdef _WIN32
+    return true;
+#else
+    return false;
+#endif
+}
+
+void setTarget(const std::string &name) {
+    std::string host = llvm::sys::getDefaultTargetTriple();
+    std::string t = name;
+    if (name.empty()) t = host;
+    else if (name == "windows") t = hostIsWindows() ? host : "x86_64-w64-mingw32";
+    else if (name == "linux") t = "x86_64-unknown-linux-gnu";
+    g_target.triple = llvm::Triple(llvm::Triple::normalize(t));
+    g_target.windows = g_target.triple.isOSWindows();
+    g_target.msvc = g_target.triple.isWindowsMSVCEnvironment();
+    g_target.cross = llvm::Triple(llvm::Triple::normalize(host)).getOS() != g_target.triple.getOS();
+    g_target.exe = g_target.windows ? ".exe" : "";
+
+    // FINCH_CC chooses the C compiler for any target; CC only when not cross-compiling.
+    if (const char *fc = std::getenv("FINCH_CC")) g_target.cc = fc;
+    else if (!g_target.cross && std::getenv("CC")) g_target.cc = std::getenv("CC");
+    else if (g_target.cross && g_target.windows) g_target.cc = "x86_64-w64-mingw32-gcc";
+    else if (g_target.cross) g_target.cc = "clang --target=" + g_target.triple.str();
+    else if (hostIsWindows()) g_target.cc = "clang";
+    else g_target.cc = "cc";
+}
+
+std::string shellQuote(const std::string &s) {
+#ifdef _WIN32
+    // cmd.exe: double quotes; a " inside a file name is impossible on Windows
+    return "\"" + s + "\"";
+#else
+    std::string out = "'";
+    for (char ch : s) out += ch == '\'' ? std::string("'\\''") : std::string(1, ch);
+    return out + "'";
+#endif
+}
+
+static int exitStatus(int status) {
+#ifdef _WIN32
+    return status;
+#else
+    if (status == -1) return -1;
+    if (WIFEXITED(status)) return WEXITSTATUS(status);
+    if (WIFSIGNALED(status)) return 128 + WTERMSIG(status);
+    return -1;
+#endif
+}
+
+int capture(const std::string &cmd, std::string &output) {
+    FILE *p = popen((cmd + " 2>&1").c_str(), "r");
+    if (!p) return -1;
+    char buf[4096];
+    size_t n;
+    while ((n = std::fread(buf, 1, sizeof buf, p)) > 0) output.append(buf, n);
+    return exitStatus(pclose(p));
+}
+
+int runCommand(const std::string &cmd, std::string *crash) {
+    std::fflush(stdout);
+    int status = std::system(cmd.c_str());
+#ifndef _WIN32
+    if (crash && status != -1 && WIFSIGNALED(status)) *crash = strsignal(WTERMSIG(status));
+#else
+    // a crashed Windows program exits with an NTSTATUS code like 0xC0000005
+    if (crash && (unsigned)status >= 0xC0000000u) {
+        char buf[64];
+        std::snprintf(buf, sizeof buf, "exception 0x%08X%s", (unsigned)status,
+                      (unsigned)status == 0xC0000005u ? " (access violation)" : (unsigned)status == 0xC00000FDu ? " (stack overflow)" : "");
+        *crash = buf;
+    }
+#endif
+    return exitStatus(status);
+}
+
+const char *nullDevice() { return hostIsWindows() ? "NUL" : "/dev/null"; }
+
+std::string cacheDir() {
+#ifdef _WIN32
+    if (const char *l = std::getenv("LOCALAPPDATA")) return std::string(l) + "\\finch";
+    if (const char *t = std::getenv("TEMP")) return std::string(t) + "\\finch";
+    return "finch-cache";
+#else
+    if (const char *x = std::getenv("XDG_CACHE_HOME")) return std::string(x) + "/finch";
+    if (const char *h = std::getenv("HOME")) return std::string(h) + "/.cache/finch";
+    return "/tmp/finch-cache";
+#endif
+}
+
+char pathListSeparator() { return hostIsWindows() ? ';' : ':'; }
+
+std::string dirOf(const std::string &path) {
+    size_t slash = hostIsWindows() ? path.find_last_of("/\\") : path.find_last_of('/');
+    return slash == std::string::npos ? "." : path.substr(0, slash);
+}