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The result of E1 >> E2 is E1 right-shifted E2 bit positions. If E1 has an unsigned type or if E1 has a signed type and a nonnegative value, the value of the result is the integral part of the quotient of E1 / 2E2. If E1 has a signed type and a negative value, the resulting value is implementation defined and may be either an arithmetic (signed) shift, as depicted in Figure 5—2, :
or a logical (unsigned) shift, as depicted in Figure 5—3
Figure 5—2. Arithmetic (signed) shift.:
This noncompliant code example fails to test whether the right operand is greater than or equal to the width of the promoted left operand, allowing undefined behavior.
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