The tests discovered a real bug. The WINRT_IMPL_SHIM macro only keeps…

… the temporary alive until the semicolon. Remove that macro from where I need to call the check method to fix this crash
microsoft · Oct 29, 2024 · 4a1dd03 · 4a1dd03
1 parent 83c846b
commit 4a1dd03
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Showing 2 changed files with 14 additions and 10 deletions.
diff --git a/cppwinrt/code_writers.h b/cppwinrt/code_writers.h
@@ -1131,19 +1131,21 @@ namespace cppwinrt
                 // we intentionally ignore errors when unregistering event handlers to be consistent with event_revoker
                 format = R"(    template <typename D%> auto consume_%<D%>::%(%) const noexcept
     {%
-        const auto castedResult = WINRT_IMPL_SHIM(%);
-        check_cast_result(castedResult);
-        castedResult->%(%);%
+        const auto castedResult = static_cast<% const&>(static_cast<D const&>(*this));
+        const auto abiType = *(abi_t<%>**)&castedResult;
+        check_cast_result(abiType);
+        abiType->%(%);%
     }
 )";
             }
             else
             {
                 format = R"(    template <typename D%> auto consume_%<D%>::%(%) const noexcept
     {%
-        const auto castedResult = WINRT_IMPL_SHIM(%);
-        check_cast_result(castedResult);
-        WINRT_VERIFY_(0, castedResult->%(%));%
+        const auto castedResult = static_cast<% const&>(static_cast<D const&>(*this));
+        const auto abiType = *(abi_t<%>**)&castedResult;
+        check_cast_result(abiType);
+        WINRT_VERIFY_(0, abiType->%(%));%
     }
 )";
             }
@@ -1152,9 +1154,10 @@ namespace cppwinrt
         {
             format = R"(    template <typename D%> auto consume_%<D%>::%(%) const
     {%
-        const auto castedResult = WINRT_IMPL_SHIM(%);
-        check_cast_result(castedResult);
-        check_hresult(castedResult->%(%));%
+        const auto castedResult = static_cast<% const&>(static_cast<D const&>(*this));
+        const auto abiType = *(abi_t<%>**)&castedResult;
+        check_cast_result(abiType);
+        check_hresult(abiType->%(%));%
     }
 )";
         }
@@ -1167,6 +1170,7 @@ namespace cppwinrt
             bind<write_consume_params>(signature),
             bind<write_consume_return_type>(signature, false),
             type,
+            type,
             get_abi_name(method),
             bind<write_abi_args>(signature),
             bind<write_consume_return_statement>(signature));

diff --git a/strings/base_error.h b/strings/base_error.h
@@ -530,7 +530,7 @@ WINRT_EXPORT namespace winrt
     }
 
     template <typename T>
-    WINRT_IMPL_NOINLINE void check_cast_result(T const& from WINRT_IMPL_SOURCE_LOCATION_ARGS)
+    WINRT_IMPL_NOINLINE void check_cast_result(T* from WINRT_IMPL_SOURCE_LOCATION_ARGS)
     {
         if (!from)
         {