diff --git a/src/xenia/kernel/modules/xam/xam_info.cc b/src/xenia/kernel/modules/xam/xam_info.cc
index 7010388f1..c847d7bbe 100644
--- a/src/xenia/kernel/modules/xam/xam_info.cc
+++ b/src/xenia/kernel/modules/xam/xam_info.cc
@@ -22,7 +22,7 @@ using namespace xe::kernel::xam;
 namespace {
 
 
-void XGetAVPack_shim(
+SHIM_CALL XGetAVPack_shim(
     xe_ppc_state_t* ppc_state, XamState* state) {
   // DWORD
   // Not sure what the values are for this, but 6 is VGA.
@@ -33,7 +33,7 @@ void XGetAVPack_shim(
 }
 
 
-void XGetGameRegion_shim(
+SHIM_CALL XGetGameRegion_shim(
     xe_ppc_state_t* ppc_state, XamState* state) {
   XELOGD("XGetGameRegion()");
 
@@ -41,7 +41,7 @@ void XGetGameRegion_shim(
 }
 
 
-void XGetLanguage_shim(
+SHIM_CALL XGetLanguage_shim(
     xe_ppc_state_t* ppc_state, XamState* state) {
   XELOGD("XGetLanguage()");
 
diff --git a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_hal.cc b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_hal.cc
index bf044944a..37849c695 100644
--- a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_hal.cc
+++ b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_hal.cc
@@ -21,7 +21,7 @@ using namespace xe::kernel::xboxkrnl;
 namespace {
 
 
-void HalReturnToFirmware_shim(
+SHIM_CALL HalReturnToFirmware_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // void
   // IN FIRMWARE_REENTRY  Routine
diff --git a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_memory.cc b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_memory.cc
index e3ee7fce6..468152e84 100644
--- a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_memory.cc
+++ b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_memory.cc
@@ -21,7 +21,7 @@ using namespace xe::kernel::xboxkrnl;
 namespace {
 
 
-void NtAllocateVirtualMemory_shim(
+SHIM_CALL NtAllocateVirtualMemory_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // NTSTATUS
   // _Inout_  PVOID *BaseAddress,
@@ -96,7 +96,7 @@ void NtAllocateVirtualMemory_shim(
   SHIM_SET_RETURN(X_STATUS_SUCCESS);
 }
 
-void NtFreeVirtualMemory_shim(
+SHIM_CALL NtFreeVirtualMemory_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // NTSTATUS
   // _Inout_  PVOID *BaseAddress,
diff --git a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_module.cc b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_module.cc
index 4c9553e1e..b43da3100 100644
--- a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_module.cc
+++ b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_module.cc
@@ -23,14 +23,14 @@ using namespace xe::kernel::xboxkrnl;
 namespace {
 
 
-// void ExGetXConfigSetting_shim(
+// SHIM_CALL ExGetXConfigSetting_shim(
 //     xe_ppc_state_t* ppc_state, KernelState* state) {
 //   // ?
 //   SHIM_SET_RETURN(0);
 // }
 
 
-void XexCheckExecutablePrivilege_shim(
+SHIM_CALL XexCheckExecutablePrivilege_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // BOOL
   // DWORD Privilege
@@ -62,7 +62,7 @@ void XexCheckExecutablePrivilege_shim(
 }
 
 
-void XexGetModuleHandle_shim(
+SHIM_CALL XexGetModuleHandle_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // BOOL
   // LPCSZ ModuleName
@@ -90,12 +90,12 @@ void XexGetModuleHandle_shim(
 }
 
 
-// void XexGetModuleSection_shim(
+// SHIM_CALL XexGetModuleSection_shim(
 //     xe_ppc_state_t* ppc_state, KernelState* state) {
 // }
 
 
-// void XexGetProcedureAddress_shim(
+// SHIM_CALL XexGetProcedureAddress_shim(
 //     xe_ppc_state_t* ppc_state, KernelState* state) {
 // }
 
diff --git a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_rtl.cc b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_rtl.cc
index 8228e0887..7e6af6cab 100644
--- a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_rtl.cc
+++ b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_rtl.cc
@@ -24,7 +24,7 @@ namespace {
 
 
 // http://msdn.microsoft.com/en-us/library/ff561778
-void RtlCompareMemory_shim(
+SHIM_CALL RtlCompareMemory_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // SIZE_T
   // _In_  const VOID *Source1,
@@ -57,7 +57,7 @@ void RtlCompareMemory_shim(
 }
 
 // http://msdn.microsoft.com/en-us/library/ff552123
-void RtlCompareMemoryUlong_shim(
+SHIM_CALL RtlCompareMemoryUlong_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // SIZE_T
   // _In_  PVOID Source,
@@ -97,7 +97,7 @@ void RtlCompareMemoryUlong_shim(
 }
 
 // http://msdn.microsoft.com/en-us/library/ff552263
-void RtlFillMemoryUlong_shim(
+SHIM_CALL RtlFillMemoryUlong_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // VOID
   // _Out_  PVOID Destination,
@@ -132,7 +132,7 @@ void RtlFillMemoryUlong_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ff561918
-void RtlInitAnsiString_shim(
+SHIM_CALL RtlInitAnsiString_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // VOID
   // _Out_     PANSI_STRING DestinationString,
@@ -153,7 +153,7 @@ void RtlInitAnsiString_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ff561899
-void RtlFreeAnsiString_shim(
+SHIM_CALL RtlFreeAnsiString_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // VOID
   // _Inout_  PANSI_STRING AnsiString
@@ -180,7 +180,7 @@ void RtlFreeAnsiString_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ff561934
-void RtlInitUnicodeString_shim(
+SHIM_CALL RtlInitUnicodeString_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // VOID
   // _Out_     PUNICODE_STRING DestinationString,
@@ -202,7 +202,7 @@ void RtlInitUnicodeString_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ff561903
-void RtlFreeUnicodeString_shim(
+SHIM_CALL RtlFreeUnicodeString_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // VOID
   // _Inout_  PUNICODE_STRING UnicodeString
@@ -222,7 +222,7 @@ void RtlFreeUnicodeString_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ff562969
-void RtlUnicodeStringToAnsiString_shim(
+SHIM_CALL RtlUnicodeStringToAnsiString_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // NTSTATUS
   // _Inout_  PANSI_STRING DestinationString,
@@ -250,7 +250,7 @@ void RtlUnicodeStringToAnsiString_shim(
 }
 
 
-void RtlImageXexHeaderField_shim(
+SHIM_CALL RtlImageXexHeaderField_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // PVOID
   // PVOID XexHeaderBase
@@ -340,7 +340,7 @@ typedef struct {
 }
 
 
-void RtlInitializeCriticalSection_shim(
+SHIM_CALL RtlInitializeCriticalSection_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // VOID
   // _Out_  LPCRITICAL_SECTION lpCriticalSection
@@ -357,7 +357,7 @@ void RtlInitializeCriticalSection_shim(
 }
 
 
-void RtlInitializeCriticalSectionAndSpinCount_shim(
+SHIM_CALL RtlInitializeCriticalSectionAndSpinCount_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // NTSTATUS
   // _Out_  LPCRITICAL_SECTION lpCriticalSection,
@@ -382,7 +382,7 @@ void RtlInitializeCriticalSectionAndSpinCount_shim(
 }
 
 
-void RtlEnterCriticalSection_shim(
+SHIM_CALL RtlEnterCriticalSection_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // VOID
   // _Inout_  LPCRITICAL_SECTION lpCriticalSection
@@ -421,7 +421,7 @@ spin:
 }
 
 
-void RtlTryEnterCriticalSection_shim(
+SHIM_CALL RtlTryEnterCriticalSection_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // DWORD
   // _Inout_  LPCRITICAL_SECTION lpCriticalSection
@@ -452,7 +452,7 @@ void RtlTryEnterCriticalSection_shim(
 }
 
 
-void RtlLeaveCriticalSection_shim(
+SHIM_CALL RtlLeaveCriticalSection_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // VOID
   // _Inout_  LPCRITICAL_SECTION lpCriticalSection
diff --git a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_threading.cc b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_threading.cc
index f52a4c513..20690dddd 100644
--- a/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_threading.cc
+++ b/src/xenia/kernel/modules/xboxkrnl/xboxkrnl_threading.cc
@@ -55,7 +55,7 @@ namespace {
 // }
 
 
-void ExCreateThread_shim(
+SHIM_CALL ExCreateThread_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // DWORD
   // LPHANDLE Handle,
@@ -107,7 +107,7 @@ void ExCreateThread_shim(
 }
 
 
-void KeGetCurrentProcessType_shim(
+SHIM_CALL KeGetCurrentProcessType_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // DWORD
 
@@ -125,7 +125,7 @@ void KeGetCurrentProcessType_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ms686801
-void KeTlsAlloc_shim(
+SHIM_CALL KeTlsAlloc_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // DWORD
 
@@ -150,7 +150,7 @@ void KeTlsAlloc_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ms686804
-void KeTlsFree_shim(
+SHIM_CALL KeTlsFree_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // BOOL
   // _In_  DWORD dwTlsIndex
@@ -179,7 +179,7 @@ void KeTlsFree_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ms686812
-void KeTlsGetValue_shim(
+SHIM_CALL KeTlsGetValue_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // LPVOID
   // _In_  DWORD dwTlsIndex
@@ -208,7 +208,7 @@ void KeTlsGetValue_shim(
 
 
 // http://msdn.microsoft.com/en-us/library/ms686818
-void KeTlsSetValue_shim(
+SHIM_CALL KeTlsSetValue_shim(
     xe_ppc_state_t* ppc_state, KernelState* state) {
   // BOOL
   // _In_      DWORD dwTlsIndex,
diff --git a/src/xenia/kernel/shim_utils.h b/src/xenia/kernel/shim_utils.h
index 22ed3b089..29e80d9c0 100644
--- a/src/xenia/kernel/shim_utils.h
+++ b/src/xenia/kernel/shim_utils.h
@@ -22,6 +22,8 @@ namespace xe {
 namespace kernel {
 
 
+#define SHIM_CALL             void _cdecl
+
 #define SHIM_MEM_ADDR(a)      (ppc_state->membase + a)
 
 #define SHIM_MEM_16(a)        (uint16_t)XEGETUINT16BE(SHIM_MEM_ADDR(a));
@@ -38,6 +40,7 @@ namespace kernel {
 #define SHIM_GET_ARG_64(n)    SHIM_GPR_64(3 + n)
 #define SHIM_SET_RETURN(v)    SHIM_SET_GPR_64(3, v)
 
+
 }  // namespace kernel
 }  // namespace xe