Use /ALTERNATENAME instead of checked-in OBJ files generated by aliasobj

stl/CMakeLists.txt

@@ -433,11 +433,6 @@ set(SATELLITE_DLL_SOURCES
     ${CMAKE_CURRENT_LIST_DIR}/src/dllmain_satellite.cpp
     )
 
-add_library(std_init_once_begin_initialize OBJECT IMPORTED)
-add_library(std_init_once_complete OBJECT IMPORTED)
-set_target_properties(std_init_once_begin_initialize PROPERTIES IMPORTED_OBJECTS "${CMAKE_CURRENT_LIST_DIR}/aliases/${VCLIBS_I386_OR_AMD64}/std_init_once_begin_initialize.obj")
-set_target_properties(std_init_once_complete PROPERTIES IMPORTED_OBJECTS "${CMAKE_CURRENT_LIST_DIR}/aliases/${VCLIBS_I386_OR_AMD64}/std_init_once_complete.obj")
-
 add_compile_definitions(_CRTBLD _VCRT_ALLOW_INTERNALS _HAS_OLD_IOSTREAMS_MEMBERS=1 _STL_CONCRT_SUPPORT)
 
 include_directories(BEFORE
@@ -495,7 +490,7 @@ function(add_stl_dlls D_SUFFIX THIS_CONFIG_DEFINITIONS THIS_CONFIG_COMPILE_OPTIO
     target_link_libraries(msvcp_2${D_SUFFIX}_objects PRIVATE Boost::math)
 
     add_library(msvcp_2${D_SUFFIX} SHARED)
-    target_link_libraries(msvcp_2${D_SUFFIX} PRIVATE msvcp_2${D_SUFFIX}_objects msvcp${D_SUFFIX}_satellite_objects msvcp${D_SUFFIX}_implib_objects std_init_once_begin_initialize std_init_once_complete "msvcp${D_SUFFIX}" "${TOOLSET_LIB}/vcruntime${D_SUFFIX}.lib" "${TOOLSET_LIB}/msvcrt${D_SUFFIX}.lib" "ucrt${D_SUFFIX}.lib")
+    target_link_libraries(msvcp_2${D_SUFFIX} PRIVATE msvcp_2${D_SUFFIX}_objects msvcp${D_SUFFIX}_satellite_objects msvcp${D_SUFFIX}_implib_objects "msvcp${D_SUFFIX}" "${TOOLSET_LIB}/vcruntime${D_SUFFIX}.lib" "${TOOLSET_LIB}/msvcrt${D_SUFFIX}.lib" "ucrt${D_SUFFIX}.lib")
     set_target_properties(msvcp_2${D_SUFFIX} PROPERTIES ARCHIVE_OUTPUT_NAME "msvcp140_2${D_SUFFIX}${VCLIBS_SUFFIX}")
     set_target_properties(msvcp_2${D_SUFFIX} PROPERTIES ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
     set_target_properties(msvcp_2${D_SUFFIX} PROPERTIES OUTPUT_NAME "msvcp140_2${D_SUFFIX}${VCLIBS_SUFFIX}")
@@ -537,7 +532,7 @@ function(add_stl_dlls D_SUFFIX THIS_CONFIG_DEFINITIONS THIS_CONFIG_COMPILE_OPTIO
 
     # import library
     add_library(msvcp${D_SUFFIX}_implib STATIC ${HEADERS})
-    target_link_libraries(msvcp${D_SUFFIX}_implib msvcp${D_SUFFIX}_implib_objects std_init_once_begin_initialize std_init_once_complete)
+    target_link_libraries(msvcp${D_SUFFIX}_implib msvcp${D_SUFFIX}_implib_objects)
     add_dependencies(msvcp${D_SUFFIX}_implib msvcp${D_SUFFIX} msvcp_1${D_SUFFIX} msvcp_2${D_SUFFIX} msvcp${D_SUFFIX}_atomic_wait msvcp${D_SUFFIX}_codecvt_ids)
     set_target_properties(msvcp${D_SUFFIX}_implib PROPERTIES STATIC_LIBRARY_OPTIONS "/NOLOGO;/NODEFAULTLIB;/IGNORE:4006;$<TARGET_LINKER_FILE:msvcp${D_SUFFIX}>;$<TARGET_LINKER_FILE:msvcp_1${D_SUFFIX}>;$<TARGET_LINKER_FILE:msvcp_2${D_SUFFIX}>;$<TARGET_LINKER_FILE:msvcp${D_SUFFIX}_codecvt_ids>;$<TARGET_LINKER_FILE:msvcp${D_SUFFIX}_atomic_wait>")
     set_target_properties(msvcp${D_SUFFIX}_implib PROPERTIES ARCHIVE_OUTPUT_NAME "msvcprt${D_SUFFIX}")
@@ -554,7 +549,7 @@ function(add_stl_statics FLAVOR_SUFFIX THIS_CONFIG_DEFINITIONS THIS_CONFIG_COMPI
     add_library(libcpmt${FLAVOR_SUFFIX} STATIC ${HEADERS} ${IMPLIB_SOURCES} ${SOURCES} ${INITIALIZER_SOURCES} ${STATIC_SOURCES})
     target_compile_definitions(libcpmt${FLAVOR_SUFFIX} PRIVATE "${THIS_CONFIG_DEFINITIONS};_ANNOTATE_VECTOR")
     target_compile_options(libcpmt${FLAVOR_SUFFIX} PRIVATE "${THIS_CONFIG_COMPILE_OPTIONS};/EHsc")
-    target_link_libraries(libcpmt${FLAVOR_SUFFIX} PRIVATE Boost::math libcpmt${FLAVOR_SUFFIX}_eha std_init_once_begin_initialize std_init_once_complete)
+    target_link_libraries(libcpmt${FLAVOR_SUFFIX} PRIVATE Boost::math libcpmt${FLAVOR_SUFFIX}_eha)
 endfunction()
 
 add_stl_statics("" "_ITERATOR_DEBUG_LEVEL=0" "${VCLIBS_RELEASE_OPTIONS}")

stl/inc/mutex

@@ -495,13 +495,14 @@ public:
 };
 #endif // _HAS_CXX17
 
-#ifdef _M_CEE
+#if defined(_M_CEE) || defined(_M_ARM64EC) || defined(_M_HYBRID) \
+    || defined(__clang__) // TRANSITION, Clang doesn't recognize /ALTERNATENAME, not yet reported
 #define _WINDOWS_API              __stdcall
 #define _RENAME_WINDOWS_API(_Api) _Api##_clr
-#else // ^^^ _M_CEE // !_M_CEE vvv
+#else // ^^^ use forwarders / use /ALTERNATENAME vvv
 #define _WINDOWS_API              __declspec(dllimport) __stdcall
 #define _RENAME_WINDOWS_API(_Api) _Api
-#endif // _M_CEE
+#endif // ^^^ use /ALTERNATENAME ^^^
 
 // WINBASEAPI
 // BOOL
@@ -526,6 +527,8 @@ extern "C" _NODISCARD int _WINDOWS_API _RENAME_WINDOWS_API(__std_init_once_begin
 extern "C" _NODISCARD int _WINDOWS_API _RENAME_WINDOWS_API(__std_init_once_complete)(
     void** _LpInitOnce, unsigned long _DwFlags, void* _LpContext) noexcept;
 
+extern "C" [[noreturn]] void __stdcall __std_init_once_link_alternate_names_and_abort() noexcept;
+
 // #define RTL_RUN_ONCE_INIT_FAILED    0x00000004UL
 // #define INIT_ONCE_INIT_FAILED       RTL_RUN_ONCE_INIT_FAILED
 _INLINE_VAR constexpr unsigned long _Init_once_init_failed = 0x4UL;
@@ -535,7 +538,7 @@ struct _Init_once_completer {
     unsigned long _DwFlags;
     ~_Init_once_completer() {
         if (_RENAME_WINDOWS_API(__std_init_once_complete)(&_Once._Opaque, _DwFlags, nullptr) == 0) {
-            _CSTD abort();
+            __std_init_once_link_alternate_names_and_abort();
         }
     }
 };

stl/msbuild/stl_base/stl.files.settings.targets

@@ -186,11 +186,6 @@ SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
         </BuildFiles>
     </ItemGroup>
 
-    <ItemGroup Condition="'$(CrtBuildModelIsDll)' != 'true'">
-      <Lib Include="$(MSBuildThisFileDirectory)\..\..\aliases\$(BuildArchitecture)\std_init_once_begin_initialize.obj" />
-      <Lib Include="$(MSBuildThisFileDirectory)\..\..\aliases\$(BuildArchitecture)\std_init_once_complete.obj" />
-    </ItemGroup>
-
     <Choose>
       <When Condition="'$(CrtBuildModel)' != 'md'">
         <!-- Only check exports of release, DLL, builds -->

stl/msbuild/stl_post/msvcp_post.settings.targets

@@ -67,8 +67,6 @@ SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
         <Lib Include="$(CrtLibPath)\msvcprt$(BuildSuffix)_atomic_wait$(ClrLibSuffix).lib">
             <IncludeInChameleonLib>false</IncludeInChameleonLib>
         </Lib>
-        <Lib Include="$(MSBuildThisFileDirectory)\..\..\aliases\$(BuildArchitecture)\std_init_once_begin_initialize.obj" />
-        <Lib Include="$(MSBuildThisFileDirectory)\..\..\aliases\$(BuildArchitecture)\std_init_once_complete.obj" />
     </ItemGroup>
 
     <Import Project="$(VCToolsRootPath)\crt\crt_build.targets"/>

stl/src/xonce2.cpp

@@ -3,6 +3,7 @@
 
 #include <yvals_core.h>
 
+#include <stdlib.h>
 #include <synchapi.h>
 
 // This must be as small as possible, because its contents are
@@ -11,7 +12,8 @@
 // In particular, basic_string must not be included here.
 
 // Provides forwarders for InitOnceBeginInitialize and InitOnceComplete for
-// environments that can't use aliasobj, like /clr.
+// environments that can't use /ALTERNATENAME.
+// They were originally specific to /clr but are now used in other scenarios.
 
 _EXTERN_C
 
@@ -24,4 +26,20 @@ int __stdcall __std_init_once_complete_clr(void** _LpInitOnce, unsigned long _Dw
     return InitOnceComplete(reinterpret_cast<LPINIT_ONCE>(_LpInitOnce), _DwFlags, _LpContext);
 }
 
+[[noreturn]] void __stdcall __std_init_once_link_alternate_names_and_abort() noexcept {
+    _CSTD abort();
+}
+
+#if defined(_M_ARM64EC) || defined(_M_HYBRID)
+// <mutex> uses the forwarder fallbacks for ARM64EC and CHPE.
+#elif defined(_M_IX86)
+#pragma comment(linker, "/ALTERNATENAME:__imp____std_init_once_begin_initialize@16=__imp__InitOnceBeginInitialize@16")
+#pragma comment(linker, "/ALTERNATENAME:__imp____std_init_once_complete@12=__imp__InitOnceComplete@12")
+#elif defined(_M_X64) || defined(_M_ARM) || defined(_M_ARM64)
+#pragma comment(linker, "/ALTERNATENAME:__imp___std_init_once_begin_initialize=__imp_InitOnceBeginInitialize")
+#pragma comment(linker, "/ALTERNATENAME:__imp___std_init_once_complete=__imp_InitOnceComplete")
+#else // ^^^ known architecture / unknown architecture vvv
+#error Unknown architecture
+#endif // ^^^ unknown architecture ^^^
+
 _END_EXTERN_C