3 files changed, 12 insertions, 12 deletions
diff --git a/winsup/cygwin/include/cygwin/types.h b/winsup/cygwin/include/cygwin/types.h
index 69bfa2056..caa826fce 100644
--- a/winsup/cygwin/include/cygwin/types.h
+++ b/winsup/cygwin/include/cygwin/types.h
@@ -61,14 +61,14 @@ typedef __gid16_t gid_t;
 
 #if !defined(__INSIDE_CYGWIN__) || !defined(__cplusplus)
 
-typedef void *pthread_t;
-typedef void *pthread_mutex_t;
+typedef struct __pthread_t {char __dummy;} *pthread_t;
+typedef struct __pthread_mutex_t {char __dummy;} *pthread_mutex_t;
 
-typedef void *pthread_key_t;
-typedef void *pthread_attr_t;
-typedef void *pthread_mutexattr_t;
-typedef void *pthread_condattr_t;
-typedef void *pthread_cond_t;
+typedef struct __pthread_key_t {char __dummy;} *pthread_key_t;
+typedef struct __pthread_attr_t {char __dummy;} *pthread_attr_t;
+typedef struct __pthread_mutexattr_t {char __dummy;} *pthread_mutexattr_t;
+typedef struct __pthread_condattr_t {char __dummy;} *pthread_condattr_t;
+typedef struct __pthread_cond_t {char __dummy;} *pthread_cond_t;
 
   /* These variables are not user alterable. This means you!. */
 typedef struct
@@ -77,8 +77,8 @@ typedef struct
   int state;
 }
 pthread_once_t;
-typedef void *pthread_rwlock_t;
-typedef void *pthread_rwlockattr_t;
+typedef struct __pthread_rwlock_t {char __dummy;} *pthread_rwlock_t;
+typedef struct __pthread_rwlockattr_t {char __dummy;} *pthread_rwlockattr_t;
 
 #else
 
diff --git a/winsup/cygwin/include/pthread.h b/winsup/cygwin/include/pthread.h
index 0dff00053..b1afe9300 100644
--- a/winsup/cygwin/include/pthread.h
+++ b/winsup/cygwin/include/pthread.h
@@ -44,7 +44,7 @@ extern "C"
 #define PTHREAD_CANCEL_DISABLE 1
 #define PTHREAD_CANCELED ((void *)-1)
 /* this should be a value that can never be a valid address */
-#define PTHREAD_COND_INITIALIZER (void *)21
+#define PTHREAD_COND_INITIALIZER (pthread_cond_t)21
 #define PTHREAD_CREATE_DETACHED 1
 /* the default : joinable */
 #define PTHREAD_CREATE_JOINABLE 0
@@ -54,7 +54,7 @@ extern "C"
 #define PTHREAD_MUTEX_RECURSIVE 1
 #define PTHREAD_MUTEX_DEFAULT PTHREAD_MUTEX_ERRORCHECK
 /* this should be too low to ever be a valid address */
-#define PTHREAD_MUTEX_INITIALIZER (void *)20
+#define PTHREAD_MUTEX_INITIALIZER (pthread_mutex_t)20
 #define PTHREAD_ONCE_INIT { PTHREAD_MUTEX_INITIALIZER, 0 }
 #define PTHREAD_PRIO_INHERIT
 #define PTHREAD_PRIO_NONE
diff --git a/winsup/cygwin/include/semaphore.h b/winsup/cygwin/include/semaphore.h
index 6dbfa09ac..500b8f7a4 100644
--- a/winsup/cygwin/include/semaphore.h
+++ b/winsup/cygwin/include/semaphore.h
@@ -21,7 +21,7 @@ extern "C"
 #endif
 
 #ifndef __INSIDE_CYGWIN__
-  typedef void *sem_t;
+  typedef struct __sem_t {char __dummy;} *sem_t;
 #endif
 
 #define SEM_FAILED 0