(openoffice) 16/20: bridges/msvc_win64: pass simple argument values, not the temp's address

[pe...@apache.org]

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leginee pushed a commit to branch bazel-migration
in repository https://gitbox.apache.org/repos/asf/openoffice.git

commit c671a9c6a1eeb5154ea2990db985535761436919
Author: Peter Kovacs <pe...@apache.org>
AuthorDate: Mon Jul 27 07:06:55 2026 +0200

    bridges/msvc_win64: pass simple argument values, not the temp's address
    
    uno2cpp.cxx converts each simple by-value argument into an 8-byte alloca
    temp and stores the pointer in pCppArgs[nPos]:
    
        uno_copyAndConvertData( pCppArgs[nPos] = alloca( 8 ), ... );
    
    Copying the value into the outgoing slot therefore has to dereference that
    pointer.  The marshalling switch used &pCppArgs[nPos] instead, which reads
    the pCppArgs array slot itself, i.e. the temp's address -- so every HYPER,
    LONG, ENUM, SHORT, CHAR, BOOLEAN, BYTE, FLOAT and DOUBLE parameter reached
    the callee as a stack address (or its low 16/32 bits) rather than a value.
    
    The same expression is correct in the complex/ref branch, where the pointer
    IS the argument; written there as (sal_uInt64)pCppArgs[nPos] to make the
    difference between the two branches obvious.
    
    This only affects calls that cross between the uno and cpp environments, so
    a pure-C++ session never trips it; it surfaces via pyuno and the invocation
    adapters.
    
    Co-Authored-By: Claude Opus 5 <no...@anthropic.com>
---
 .../source/cpp_uno/msvc_win64_x86-64/uno2cpp.cxx       | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/main/bridges/source/cpp_uno/msvc_win64_x86-64/uno2cpp.cxx b/main/bridges/source/cpp_uno/msvc_win64_x86-64/uno2cpp.cxx
index 2f8e80ca4d..b9e43adb45 100644
--- a/main/bridges/source/cpp_uno/msvc_win64_x86-64/uno2cpp.cxx
+++ b/main/bridges/source/cpp_uno/msvc_win64_x86-64/uno2cpp.cxx
@@ -105,29 +105,34 @@ static void cpp_call(
 			uno_copyAndConvertData( pCppArgs[nPos] = alloca( 8 ), pUnoArgs[nPos], pParamTypeDescr,
 									pThis->getBridge()->getUno2Cpp() );
 
+			// pCppArgs[nPos] is the alloca(8) temp above, i.e. a POINTER to the
+			// converted value -- the value is *pCppArgs[nPos].  Using
+			// &pCppArgs[nPos] would read the array slot instead, passing the
+			// temp's address as the argument.  (That form is correct only in the
+			// complex/ref branch below, where the pointer IS the argument.)
 			switch (pParamTypeDescr->eTypeClass)
 			{
 			case typelib_TypeClass_HYPER:
 			case typelib_TypeClass_UNSIGNED_HYPER:
-				*pStack++ = *(sal_uInt64*)&pCppArgs[nPos];
+				*pStack++ = *(sal_uInt64*)pCppArgs[nPos];
 				break;
 			case typelib_TypeClass_LONG:
 			case typelib_TypeClass_UNSIGNED_LONG:
 			case typelib_TypeClass_ENUM:
-				*pStack++ = *(sal_uInt32*)&pCppArgs[nPos];
+				*pStack++ = *(sal_uInt32*)pCppArgs[nPos];
 				break;
 			case typelib_TypeClass_SHORT:
 			case typelib_TypeClass_UNSIGNED_SHORT:
 			case typelib_TypeClass_CHAR:
-				*pStack++ = *(sal_uInt16*)&pCppArgs[nPos];
+				*pStack++ = *(sal_uInt16*)pCppArgs[nPos];
 				break;
 			case typelib_TypeClass_BOOLEAN:
 			case typelib_TypeClass_BYTE:
-				*pStack++ = *(sal_uInt8*)&pCppArgs[nPos];
+				*pStack++ = *(sal_uInt8*)pCppArgs[nPos];
 				break;
 			case typelib_TypeClass_FLOAT:
 			case typelib_TypeClass_DOUBLE:
-				*pStack++ = *(sal_uInt64*)&pCppArgs[nPos]; // verbatim!
+				*pStack++ = *(sal_uInt64*)pCppArgs[nPos]; // verbatim!
                 break;
             default:
                 break;
@@ -164,7 +169,8 @@ static void cpp_call(
 				// no longer needed
 				TYPELIB_DANGER_RELEASE( pParamTypeDescr );
 			}
-			*pStack++ = *(sal_uInt64*)&pCppArgs[nPos];
+			// here the POINTER is the argument (complex value passed by ref)
+			*pStack++ = (sal_uInt64)pCppArgs[nPos];
 		}
 	}