diff --git a/gb.jit/configure.ac b/gb.jit/configure.ac
index ea588ac25..94c54151a 100644
--- a/gb.jit/configure.ac
+++ b/gb.jit/configure.ac
@@ -37,7 +37,7 @@ fi
 
 GB_COMPONENT(
   jit, JIT, gb.jit, [src],
-  [GB_FIND(llvm/Config/llvm-config.h llvm-c/Core.h, `$LLVM_CONFIG --prefix` /usr/lib/llvm* /usr/local /usr, include)],
+  [GB_FIND(llvm/ExecutionEngine/JIT.h llvm/Config/llvm-config.h llvm-c/Core.h, `$LLVM_CONFIG --prefix` /usr/lib/llvm* /usr/local /usr, include)],
   [GB_FIND(libLLVM-$LLVM_VERSION.$SHLIBEXT, `$LLVM_CONFIG --prefix` /usr/lib/llvm* /usr/local /usr, lib)],
   [$C_LIB `$LLVM_CONFIG --ldflags` -lLLVM-$LLVM_VERSION],
   [-I../../main/gbx -I../../main/share -D_DEBUG -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS])
diff --git a/gb.sdl/configure.ac b/gb.sdl/configure.ac
index b7b37425a..8be3e128f 100644
--- a/gb.sdl/configure.ac
+++ b/gb.sdl/configure.ac
@@ -33,7 +33,7 @@ dnl   [$SDL_CFLAGS])
 
 GB_COMPONENT_SEARCH(
    sdl, SDL, gb.sdl, [src],
-   sdl "> 1.2.8" SDL_ttf glew xcursor,
+   sdl "> 1.2.8" SDL_ttf glew xcursor x11,
    [GB_FIND(GL/glew.h SDL_ttf.h X11/Xcursor/Xcursor.h, /usr /usr/local `sdl-config --prefix`, include include/SDL)],
    [GB_FIND(libSDL_ttf.$SHLIBEXT libGLEW.$SHLIBEXT libXcursor.$SHLIBEXT, /usr /usr/local `sdl-config --prefix`, lib)],
    [$X_LIBS -lSDL_ttf -lGLEW -lXcursor],
diff --git a/gb.xml/src/gb.xml.h b/gb.xml/src/gb.xml.h
index 8f8566af3..42f2b8e90 100644
--- a/gb.xml/src/gb.xml.h
+++ b/gb.xml/src/gb.xml.h
@@ -192,7 +192,7 @@ typedef struct
 
     void (*ThrowXMLParseException)(const char* nerror, const char *text, const size_t lenText, const char *posFailed);
 
-#if defined(OS_MACOSX) || defined(__APPLE__)
+#if defined(OS_MACOSX) || defined(__APPLE__) || defined(__CYGWIN__)
     void* (*memrchr)(const char *s, int c, size_t n);
 #endif
 
diff --git a/gb.xml/src/html/htmlmain.h b/gb.xml/src/html/htmlmain.h
index 47f68c014..98de76e13 100644
--- a/gb.xml/src/html/htmlmain.h
+++ b/gb.xml/src/html/htmlmain.h
@@ -28,7 +28,7 @@
 extern "C" XML_INTERFACE XML;
 #endif
 
-#if defined(OS_MACOSX) || defined(__APPLE__)
+#if defined(OS_MACOSX) || defined(__APPLE__) || defined(__CYGWIN__)
 #define memrchr(s, c, n) XML.memrchr(s, c, n)
 #endif
 
diff --git a/gb.xml/src/main.cpp b/gb.xml/src/main.cpp
index 56f8fbfae..425dcbc19 100644
--- a/gb.xml/src/main.cpp
+++ b/gb.xml/src/main.cpp
@@ -104,7 +104,7 @@ extern "C"
 
         (void *)ThrowXMLParseException,
 
-    #if defined(OS_MACOSX) || defined(__APPLE__)
+    #if defined(OS_MACOSX) || defined(__APPLE__) || defined(__CYGWIN__)
         (void*)memrchr,
     #endif
 
diff --git a/gb.xml/src/utils.cpp b/gb.xml/src/utils.cpp
index 94e7a00ff..61e54f153 100644
--- a/gb.xml/src/utils.cpp
+++ b/gb.xml/src/utils.cpp
@@ -28,7 +28,7 @@
 #include <stdio.h>
 #include <memory.h>
 
-#ifdef OS_MACOSX
+#if defined(OS_MACOSX) || defined(__CYGWIN__)
 void *memrchr(const char *s, int c, size_t n)
 {
     const char *start=s,*end=(s+n-1);
diff --git a/gb.xml/src/utils.h b/gb.xml/src/utils.h
index 48a08fca1..ea807aaa4 100644
--- a/gb.xml/src/utils.h
+++ b/gb.xml/src/utils.h
@@ -26,7 +26,7 @@
 
 #define CHAR_ERROR 0xFFFD // �
 
-#ifdef OS_MACOSX
+#if defined(OS_MACOSX) || defined(__CYGWIN__)
 #include <string.h>
 void *memrchr(const char *s, int c, size_t n);
 #endif