fix(windows): survive cmd.exe's 8191 character command line limit

- with big extension stacks (imagick) the link command lines exceed what
  cmd.exe allows and fail with 'The command line is too long'
- pass the collected LIBS_CLI/LIBS_CGI/LIBS_MICRO lib lists to link.exe
  through @response files, like php-src already does for its object lists
- compile the frankenphp -mthreads shim instead of generating a .bat:
  batch files run through cmd.exe and cap cgo link lines at 8191 chars,
  a real executable gets the full 32K and past that go writes a response
  file by itself; still probe-gated, still a stopgap for golang/go#80290

src/Package/Target/php/frankenphp.php

@@ -26,6 +26,55 @@ use ZM\Logger\ConsoleColor;
 
 trait frankenphp
 {
+    /**
+     * Source of the -mthreads stripping shim, see windowsCgoCompilers(). The %s
+     * placeholder receives the wrapped compiler path as a C string literal.
+     */
+    private const string MTHREADS_SHIM_C = <<<'C'
+        // Generated by static-php-cli. Drops the MinGW-only -mthreads flag Go passes to
+        // cgo (golang/go#80290) and forwards everything else to clang.
+        #include <windows.h>
+        #include <wchar.h>
+        #include <stdlib.h>
+
+        static const wchar_t compiler[] = L"%s";
+
+        int main(void)
+        {
+            const wchar_t *args = GetCommandLineW();
+            // skip our own (possibly quoted) argv[0]
+            if (*args == L'"') {
+                args++;
+                while (*args && *args != L'"') args++;
+                if (*args) args++;
+            } else {
+                while (*args && *args != L' ' && *args != L'\t') args++;
+            }
+
+            // "<compiler>" + args + trailing space so a flag at the very end still matches
+            size_t len = wcslen(compiler) + wcslen(args) + 8;
+            wchar_t *cmd = calloc(len, sizeof(wchar_t));
+            if (cmd == NULL) return 1;
+            swprintf(cmd, len, L"\"%%ls\"%%ls ", compiler, args);
+
+            // remove every space-delimited -mthreads token
+            wchar_t *p;
+            while ((p = wcsstr(cmd, L" -mthreads ")) != NULL) {
+                wmemmove(p, p + 10, wcslen(p + 10) + 1);
+            }
+
+            STARTUPINFOW si = {sizeof(si)};
+            PROCESS_INFORMATION pi;
+            if (!CreateProcessW(NULL, cmd, NULL, NULL, TRUE, 0, NULL, NULL, &si, &pi)) {
+                return 127;
+            }
+            WaitForSingleObject(pi.hProcess, INFINITE);
+            DWORD code = 1;
+            GetExitCodeProcess(pi.hProcess, &code);
+            return (int) code;
+        }
+        C;
+
     #[Stage]
     public function buildFrankenphpForUnix(TargetPackage $package, PackageInstaller $installer, ToolchainInterface $toolchain, PackageBuilder $builder): void
     {
@@ -382,8 +431,12 @@ trait frankenphp
      * Return the [CC, CXX] cgo should use to build FrankenPHP on Windows.
      *
      * Go passes the MinGW-only `-mthreads` flag to the C compiler for cgo builds;
-     * Clang >= 20 rejects it for the MSVC target. When it does, wrap Clang with
-     * a tiny .bat that strips the flag before forwarding.
+     * Clang >= 20 rejects it for the MSVC target. When it does, wrap Clang with a
+     * small compiled shim that strips the flag before forwarding. An executable and
+     * not a .bat on purpose: batch files run through cmd.exe, which caps the command
+     * line at 8191 characters, and cgo link steps with big extension stacks (imagick)
+     * blow past that. A real process gets the full ~32K limit, and beyond that Go
+     * switches to a response file by itself.
      *
      * Workaround for https://github.com/golang/go/issues/80290, remove once Go
      * stops passing the flag.
@@ -403,14 +456,17 @@ trait frankenphp
 
         logger()->info('Clang rejects -mthreads; wrapping it to strip the flag (golang/go#80290)');
         $dir = dirname($clang);
-        $cc = $package->getSourceDir() . '\cc-nothreads.bat';
-        $cxx = $package->getSourceDir() . '\cxx-nothreads.bat';
-        // %*: the whole command line; the substring replace drops the -mthreads token,
-        // preserving quoting of paths that a for-loop would mangle.
-        file_put_contents($cc, "@echo off\r\nset \"a=%*\"\r\nset \"a=%a: -mthreads = %\"\r\n\"{$dir}\\clang.exe\" %a%\r\n");
-        file_put_contents($cxx, "@echo off\r\nset \"a=%*\"\r\nset \"a=%a: -mthreads = %\"\r\n\"{$dir}\\clang++.exe\" %a%\r\n");
+        $wrappers = [];
+        foreach (['cc-nothreads' => 'clang.exe', 'cxx-nothreads' => 'clang++.exe'] as $name => $compiler) {
+            $src = $package->getSourceDir() . "\\{$name}.c";
+            $exe = $package->getSourceDir() . "\\{$name}.exe";
+            file_put_contents($src, sprintf(self::MTHREADS_SHIM_C, str_replace('\\', '\\\\', "{$dir}\\{$compiler}")));
+            cmd()->cd($package->getSourceDir())
+                ->exec('"' . $clang . '" -O2 ' . escapeshellarg($src) . ' -o ' . escapeshellarg($exe));
+            $wrappers[] = $exe;
+        }
 
-        return [$cc, $cxx];
+        return $wrappers;
     }
 
     protected function getFrankenPHPVersion(TargetPackage $package): string

src/Package/Target/php/windows.php

@@ -175,8 +175,9 @@ trait windows
             }
         }
 
+        $libs_cli = $this->makeLibsResponseFile($package, 'cli', "ws2_32.lib shell32.lib {$extra_libs}");
         cmd()->cd($package->getSourceDir())
-            ->exec("nmake /nologo {$debug_overrides}LIBS_CLI=\"ws2_32.lib shell32.lib {$extra_libs}\" EXTRA_LD_FLAGS_PROGRAM= php.exe");
+            ->exec("nmake /nologo {$debug_overrides}LIBS_CLI=\"{$libs_cli}\" EXTRA_LD_FLAGS_PROGRAM= php.exe");
 
         $this->deployWindowsBinary($builder, $package, 'php-cli');
     }
@@ -245,8 +246,9 @@ trait windows
             }
         }
 
+        $libs_cgi = $this->makeLibsResponseFile($package, 'cgi', "ws2_32.lib kernel32.lib advapi32.lib {$extra_libs}");
         cmd()->cd($package->getSourceDir())
-            ->exec("nmake /nologo {$debug_overrides}LIBS_CGI=\"ws2_32.lib kernel32.lib advapi32.lib {$extra_libs}\" EXTRA_LD_FLAGS_PROGRAM= php-cgi.exe");
+            ->exec("nmake /nologo {$debug_overrides}LIBS_CGI=\"{$libs_cgi}\" EXTRA_LD_FLAGS_PROGRAM= php-cgi.exe");
 
         $this->deployWindowsBinary($builder, $package, 'php-cgi');
     }
@@ -331,8 +333,9 @@ trait windows
 
         $fake_cli = $package->getBuildOption('with-micro-fake-cli', false) ? ' /DPHP_MICRO_FAKE_CLI' : '';
 
+        $libs_micro = $this->makeLibsResponseFile($package, 'micro', "ws2_32.lib shell32.lib {$extra_libs}");
         cmd()->cd($package->getSourceDir())
-            ->exec("nmake /nologo {$debug_overrides}LIBS_MICRO=\"ws2_32.lib shell32.lib {$extra_libs}\" CFLAGS_MICRO=\"/DZEND_ENABLE_STATIC_TSRMLS_CACHE=1{$fake_cli}\" EXTRA_LD_FLAGS_PROGRAM= micro");
+            ->exec("nmake /nologo {$debug_overrides}LIBS_MICRO=\"{$libs_micro}\" CFLAGS_MICRO=\"/DZEND_ENABLE_STATIC_TSRMLS_CACHE=1{$fake_cli}\" EXTRA_LD_FLAGS_PROGRAM= micro");
 
         $this->deployWindowsBinary($builder, $package, 'php-micro');
     }
@@ -884,4 +887,17 @@ C_CODE;
 
         $package->setOutput('PHP headers path for embed SAPI', $php_include_dir);
     }
+
+    /**
+     * Write the collected lib list into a linker response file and return the @file
+     * token for the nmake command line. With big extension stacks (imagick alone pulls
+     * in ~60 static libs) the inline list can push the whole command past cmd.exe's
+     * 8191 character limit; link.exe reads @file without any length limit.
+     */
+    private function makeLibsResponseFile(TargetPackage $package, string $sapi, string $libs): string
+    {
+        $file = "{$package->getSourceDir()}\\spc-libs-{$sapi}.rsp";
+        FileSystem::writeFile($file, $libs);
+        return "@{$file}";
+    }
 }