diff --git a/main/bridges/source/cpp_uno/gcc3_freebsd_aarch64/abi.cxx b/main/bridges/source/cpp_uno/gcc3_freebsd_aarch64/abi.cxx
index c119e4580b..08c11c4b50 100644
--- a/main/bridges/source/cpp_uno/gcc3_freebsd_aarch64/abi.cxx
+++ b/main/bridges/source/cpp_uno/gcc3_freebsd_aarch64/abi.cxx
@@ -333,10 +333,13 @@ void fill_struct( typelib_TypeDescriptionReference *pTypeRef, const sal_uInt64*
 
 sal_uInt32 align_stack_offset( sal_uInt32 offset, typelib_TypeDescriptionReference *pTypeRef )
 {
-	// On aarch64 System V ABI, the smallest stack slot is 8 bytes.
-	// Align to 8 bytes regardless of the type's natural alignment.
-	const sal_uInt32 align = 8;
-	return ( offset + align - 1 ) & ~( align - 1 );
+	typelib_TypeDescription * pTypeDescr = 0;
+	TYPELIB_DANGER_GET( &pTypeDescr, pTypeRef );
+	sal_uInt32 alignment = pTypeDescr->nAlignment;
+	TYPELIB_DANGER_RELEASE( pTypeDescr );
+	if ( alignment == 0 )
+		alignment = 1;
+	return ( offset + alignment - 1 ) & ~( alignment - 1 );
 }
 
 sal_uInt32 stack_size( typelib_TypeDescriptionReference *pTypeRef )
@@ -344,13 +347,12 @@ sal_uInt32 stack_size( typelib_TypeDescriptionReference *pTypeRef )
 	typelib_TypeDescription * pTypeDescr = 0;
 	TYPELIB_DANGER_GET( &pTypeDescr, pTypeRef );
 	sal_uInt32 size = pTypeDescr->nSize;
+	// AAPCS64 requires each stack argument to occupy a full 8-byte
+	// slot; small types are sign- or zero-extended into the slot.
+	if ( size < 8 )
+		size = 8;
 	TYPELIB_DANGER_RELEASE( pTypeDescr );
-	// In the System V AMD64 / AAPCS64 stack layout, the smallest slot that
-	// can be passed is 8 bytes (the natural stack slot size).  Round up
-	// so that small types like BOOLEAN (1B), SHORT (2B), LONG (4B) each
-	// occupy a full 8-byte slot on the overflow stack, matching what the
-	// callee's ABI expects.
-	return ( size + 7 ) & ~7u;
+	return size;
 }
 
 } // namespace aarch64
diff --git a/main/bridges/source/cpp_uno/gcc3_freebsd_aarch64/uno2cpp.cxx b/main/bridges/source/cpp_uno/gcc3_freebsd_aarch64/uno2cpp.cxx
index 8cb8c0d517..30dbd72000 100644
--- a/main/bridges/source/cpp_uno/gcc3_freebsd_aarch64/uno2cpp.cxx
+++ b/main/bridges/source/cpp_uno/gcc3_freebsd_aarch64/uno2cpp.cxx
@@ -164,12 +164,15 @@ static void callVirtualMethod(void * pThis, sal_uInt32 nVtableIndex,
 	case typelib_TypeClass_DOUBLE:
 		*reinterpret_cast<double *>( pRegisterReturn ) = fpReturn[0];
 		break;
-	case typelib_TypeClass_STRUCT:
-	case typelib_TypeClass_EXCEPTION:
-		aarch64::fill_struct( pReturnTypeRef, &gpReturn[0], &fpReturn[0], pRegisterReturn );
-		break;
 	default:
-		break;
+		{
+			sal_Int32 const nRetSize = pReturnTypeRef->pType->nSize;
+			if (bSimpleReturn && nRetSize > 0)
+			{
+				aarch64::fill_struct( pReturnTypeRef, &gpReturn[0], &fpReturn[0], pRegisterReturn );
+			}
+			break;
+		}
 	}
 }
 
@@ -353,9 +356,51 @@ static void cpp_call(
 			}
 			if ( onStack )
 			{
-				nStack = aarch64::align_stack_offset( nStack, rParam.pTypeRef );
-				sal_uInt32 size = aarch64::stack_size( rParam.pTypeRef );
-				memcpy( pStackStart + nStack, pCppArgs[nPos], size );
+			// AAPCS64: each stack argument occupies a full 8-byte slot
+			// with the value sign- or zero-extended.  The INSERT macros
+			// already perform the correct extension into a GPR-sized
+			// (sal_uInt64) scratch slot; reuse them with a local counter.
+			nStack = aarch64::align_stack_offset( nStack, rParam.pTypeRef );
+			sal_uInt32 size = aarch64::stack_size( rParam.pTypeRef );
+			sal_uInt64 scratch[1] = {0};
+			int tempNr = 0;
+			switch (pParamTypeDescr->eTypeClass)
+			{
+				case typelib_TypeClass_FLOAT:
+					INSERT_FLOAT( pCppArgs[nPos], tempNr, reinterpret_cast<double *>(scratch) );
+					break;
+				case typelib_TypeClass_DOUBLE:
+					INSERT_DOUBLE( pCppArgs[nPos], tempNr, reinterpret_cast<double *>(scratch) );
+					break;
+				case typelib_TypeClass_HYPER:
+				case typelib_TypeClass_UNSIGNED_HYPER:
+					INSERT_INT64( pCppArgs[nPos], tempNr, scratch );
+					break;
+				case typelib_TypeClass_LONG:
+					INSERT_SIGNED_INT32( pCppArgs[nPos], tempNr, scratch );
+					break;
+				case typelib_TypeClass_UNSIGNED_LONG:
+				case typelib_TypeClass_ENUM:
+					INSERT_INT32( pCppArgs[nPos], tempNr, scratch );
+					break;
+				case typelib_TypeClass_SHORT:
+					INSERT_SIGNED_INT16( pCppArgs[nPos], tempNr, scratch );
+					break;
+				case typelib_TypeClass_CHAR:
+				case typelib_TypeClass_UNSIGNED_SHORT:
+					INSERT_INT16( pCppArgs[nPos], tempNr, scratch );
+					break;
+				case typelib_TypeClass_BYTE:
+					INSERT_SIGNED_INT8( pCppArgs[nPos], tempNr, scratch );
+					break;
+				case typelib_TypeClass_BOOLEAN:
+					INSERT_INT8( pCppArgs[nPos], tempNr, scratch );
+					break;
+				default:
+					memcpy( scratch, pCppArgs[nPos], pParamTypeDescr->nSize );
+					break;
+			}
+			memcpy( pStackStart + nStack, scratch, size );
 				nStack += size;
 			}