[RTL_UNITTEST] Add RtlpInitialize

This will be compiled as a dummy in the test library, but in the unit test it will actually initialize the required RTL things.
For now it is only RtlpInitializeVectoredExceptionHandling.
This prevents a problem with the RtlVirtualUnwind test.

modules/rostests/apitests/rtl/CMakeLists.txt

@@ -1,6 +1,7 @@
 
 
 list(APPEND SOURCE
+    rtlinit.c
     RtlIntSafe.c
 )
 
@@ -43,9 +44,10 @@ endif()
 
 # RTL tests with static linkage (called unittest, so it won't run in rosautotest)
 add_executable(rtl_unittest
+    rtlinit.c
     testlist.c
     ldrstubs.c)
-target_compile_definitions(rtl_unittest PRIVATE _RTL_TEST _NTSYSTEM_)
+target_compile_definitions(rtl_unittest PRIVATE _RTL_TEST _NTSYSTEM_ TEST_STATIC)
 target_link_libraries(rtl_unittest rtl_test_lib rtl rtl_um rtl_vista wine uuid ${PSEH_LIB})
 set_module_type(rtl_unittest win32cui)
 add_importlibs(rtl_unittest msvcrt advapi32 kernel32 ntdll)

modules/rostests/apitests/rtl/rtlinit.c

@@ -0,0 +1,19 @@
+/*
+ * PROJECT:     ReactOS api tests
+ * LICENSE:     MIT (https://spdx.org/licenses/MIT)
+ * PURPOSE:     Initialization for RTL unit test
+ * COPYRIGHT:   Copyright 2026 Timo Kreuzer <[email protected]>
+ */
+
+#include <rtltests.h>
+
+VOID NTAPI RtlpInitializeVectoredExceptionHandling(VOID);
+
+VOID
+NTAPI
+RtlpInitialize(VOID)
+{
+#ifdef TEST_STATIC
+    RtlpInitializeVectoredExceptionHandling();
+#endif
+}

modules/rostests/apitests/rtl/rtltests.h

@@ -10,3 +10,7 @@
 #include <apitest.h>
 #include <ndk/ntndk.h>
 #include <strsafe.h>
+
+VOID
+NTAPI
+RtlpInitialize(VOID);