false positive unusedStructMember in unittest file

[Rob Deckers]

With version 2.17 (and earlier) I get unusedStructMember error even though the struct member is used in my GTest unittest.
error:
ModbusRegisterAssignTest.cpp:123:22: style: class member 'ModbusRegisterAssignTest::primitive_' is never used. [unusedStructMember]

    class ModbusTest : public testing::Test
{
protected:
    PrimitiveStructB primitive_;
};

TEST_F(ModbusTest, sometest)
{
    assign(strong_, std::as_const(primitive_));
}

TEST_F(ModbusTest, otherTest)
{
    ASSERT_EQ(primitive_.b1.a1, 0);
}

[CHR]

Covered by https://trac.cppcheck.net/ticket/12782