Cygwin build failed

MinGW 7.2 (x86_64) build failed

c++/src/capnp/compiler/capnp.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "lexer.h"
 #include "parser.h"
 #include "compiler.h"

c++/src/capnp/compiler/capnpc-capnp.c++

@@ -22,6 +22,10 @@
 // This program is a code generator plugin for `capnp compile` which writes the schema back to
 // stdout in roughly capnpc format.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include <capnp/schema.capnp.h>
 #include "../serialize.h"
 #include <kj/debug.h>

c++/src/capnp/compiler/evolution-test.c++

@@ -26,6 +26,10 @@
 // the types are expected to be compatible, the test also constructs an instance of the old
 // type and reads it as the new type, and vice versa.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include <capnp/compiler/grammar.capnp.h>
 #include <capnp/schema-loader.h>
 #include <capnp/message.h>

c++/src/capnp/fuzz-test.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include <capnp/test-import.capnp.h>
 #include <capnp/test-import2.capnp.h>
 #include "message.h"

c++/src/capnp/serialize-async-test.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "serialize-async.h"
 #include "serialize.h"
 #include <kj/debug.h>

c++/src/capnp/serialize-test.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "serialize.h"
 #include <kj/debug.h>
 #include <kj/compat/gtest.h>

c++/src/kj/async-io-unix.c++

@@ -22,6 +22,10 @@
 #if !_WIN32
 // For Win32 implementation, see async-io-win32.c++.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "async-io.h"
 #include "async-io-internal.h"
 #include "async-unix.h"

c++/src/kj/debug-test.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "debug.h"
 #include "exception.h"
 #include <kj/compat/gtest.h>

c++/src/kj/exception.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "exception.h"
 #include "string.h"
 #include "debug.h"

c++/src/kj/filesystem-disk-unix.c++

@@ -21,6 +21,10 @@
 
 #if !_WIN32
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "filesystem.h"
 #include "debug.h"
 #include <sys/types.h>
@@ -385,8 +389,8 @@ public:
 
     static const byte ZEROS[4096] = { 0 };
 
-#if __APPLE__
-    // Mac doesn't have pwritev().
+#if __APPLE__ || __CYGWIN__
+    // Mac & Cygwin doesn't have pwritev().
     while (size > sizeof(ZEROS)) {
       write(offset, ZEROS);
       size -= sizeof(ZEROS);

c++/src/kj/filesystem-disk-win32.c++

@@ -1094,7 +1094,7 @@ public:
       }
       KJ_DEFER({
         if (kj::isSameType<T, Directory>()) {
-          HANDLE newHandle;
+          HANDLE newHandle = nullptr;
           KJ_WIN32(newHandle = CreateFileW(
               committed ? parentDirectory.nativePath(path).begin() : tempPath.begin(),
               GENERIC_READ,

c++/src/kj/io-test.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "io.h"
 #include "debug.h"
 #include "miniposix.h"

c++/src/kj/io.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "io.h"
 #include "debug.h"
 #include "miniposix.h"

c++/src/kj/main.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "main.h"
 #include "debug.h"
 #include "arena.h"

c++/src/kj/test.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if __CYGWIN__
+#define _GNU_SOURCE
+#endif
+
 #include "test.h"
 #include "main.h"
 #include "io.h"