lvalue required as left operand of assignment

For example, in C, the syntax for a conditional expression is:

logical-OR-expression ? expression : conditional-expression
while in C++ it is:

logical-OR-expression ? expression : assignment-expression
Hence, the expression:

e = a < d ? a++ : a = d
is parsed differently in the two languages. In C, this expression is a syntax error, but many compilers parse it as:

e = ((a < d ? a++ : a) = d)
which is a semantic error, since th


e result of the conditional-expression (which might be a++) is not an lvalue. In C++, it is parsed as:

e = (a < d ? a++ : (a = d))
which is a valid expression.