diff --git a/dlls/advapi32/advapi32_misc.h b/dlls/advapi32/advapi32_misc.h
index 4d0a0e901c5..531a4f8f370 100644
--- a/dlls/advapi32/advapi32_misc.h
+++ b/dlls/advapi32/advapi32_misc.h
@@ -20,11 +20,11 @@
 #ifndef __WINE_ADVAPI32MISC_H
 #define __WINE_ADVAPI32MISC_H
 
-const char * debugstr_sid(PSID sid);
-BOOL ADVAPI_IsLocalComputer(LPCWSTR ServerName);
-BOOL ADVAPI_GetComputerSid(PSID sid);
+const char * debugstr_sid(PSID sid) DECLSPEC_HIDDEN;
+BOOL ADVAPI_IsLocalComputer(LPCWSTR ServerName) DECLSPEC_HIDDEN;
+BOOL ADVAPI_GetComputerSid(PSID sid) DECLSPEC_HIDDEN;
 
-BOOL lookup_local_wellknown_name(const LSA_UNICODE_STRING*, PSID, LPDWORD, LPWSTR, LPDWORD, PSID_NAME_USE, BOOL*);
-BOOL lookup_local_user_name(const LSA_UNICODE_STRING*, PSID, LPDWORD, LPWSTR, LPDWORD, PSID_NAME_USE, BOOL*);
+BOOL lookup_local_wellknown_name(const LSA_UNICODE_STRING*, PSID, LPDWORD, LPWSTR, LPDWORD, PSID_NAME_USE, BOOL*) DECLSPEC_HIDDEN;
+BOOL lookup_local_user_name(const LSA_UNICODE_STRING*, PSID, LPDWORD, LPWSTR, LPDWORD, PSID_NAME_USE, BOOL*) DECLSPEC_HIDDEN;
 
 #endif /* __WINE_ADVAPI32MISC_H */
diff --git a/dlls/advapi32/crypt.h b/dlls/advapi32/crypt.h
index 632e56fdbc0..9a199b50679 100644
--- a/dlls/advapi32/crypt.h
+++ b/dlls/advapi32/crypt.h
@@ -87,9 +87,9 @@ typedef struct tagCRYPTHASH
 #define MAXPROVTYPES 999
 
 extern unsigned char *CRYPT_DEShash( unsigned char *dst, const unsigned char *key,
-                                     const unsigned char *src );
+                                     const unsigned char *src ) DECLSPEC_HIDDEN;
 extern unsigned char *CRYPT_DESunhash( unsigned char *dst, const unsigned char *key,
-                                       const unsigned char *src );
+                                       const unsigned char *src ) DECLSPEC_HIDDEN;
 
 struct ustring {
     DWORD Length;
diff --git a/dlls/advapi32/service.c b/dlls/advapi32/service.c
index 96b0848b16c..2b37338c359 100644
--- a/dlls/advapi32/service.c
+++ b/dlls/advapi32/service.c
@@ -143,7 +143,7 @@ static inline DWORD multisz_cb(LPCWSTR wmultisz)
  * RPC connection with services.exe
  */
 
-handle_t __RPC_USER MACHINE_HANDLEW_bind(MACHINE_HANDLEW MachineName)
+DECLSPEC_HIDDEN handle_t __RPC_USER MACHINE_HANDLEW_bind(MACHINE_HANDLEW MachineName)
 {
     WCHAR transport[] = SVCCTL_TRANSPORT;
     WCHAR endpoint[] = SVCCTL_ENDPOINT;
@@ -170,7 +170,7 @@ handle_t __RPC_USER MACHINE_HANDLEW_bind(MACHINE_HANDLEW MachineName)
     return rpc_handle;
 }
 
-void __RPC_USER MACHINE_HANDLEW_unbind(MACHINE_HANDLEW MachineName, handle_t h)
+DECLSPEC_HIDDEN void __RPC_USER MACHINE_HANDLEW_unbind(MACHINE_HANDLEW MachineName, handle_t h)
 {
     RpcBindingFree(&h);
 }