diff --git a/src/asmjit/build.h b/src/asmjit/build.h
index b08d995..e6c4f81 100644
--- a/src/asmjit/build.h
+++ b/src/asmjit/build.h
@@ -57,6 +57,9 @@
 #elif defined(__APPLE__)
 # define ASMJIT_OS_POSIX
 # define ASMJIT_OS_MAC
+#elif defined(__CYGWIN__)
+# define ASMJIT_OS_POSIX
+# define ASMJIT_OS_CYGWIN
 #else
 # pragma message("AsmJit - Unable to detect host operating system, using ASMJIT_OS_POSIX.")
 # define ASMJIT_OS_POSIX
diff --git a/src/asmjit/x86/x86compiler.h b/src/asmjit/x86/x86compiler.h
index cff955d..ac9daaf 100644
--- a/src/asmjit/x86/x86compiler.h
+++ b/src/asmjit/x86/x86compiler.h
@@ -384,7 +384,7 @@ enum {
 
 #if defined(ASMJIT_ARCH_X64)
 enum {
-#if defined(ASMJIT_OS_WINDOWS)
+#if defined(ASMJIT_OS_WINDOWS) || defined(ASMJIT_OS_CYGWIN)
   kFuncConvHost = kX86FuncConvW64,
 #else
   kFuncConvHost = kX86FuncConvU64,