Apart from the error in the condition (&& should actually be ||), the
construct
#if !defined(A) || !A
leads to a syntax error in the C preprocessor if A is indeed not defined.
Tested-by: David Symonds <dsymonds@gmail.com> Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at> Signed-off-by: Junio C Hamano <gitster@pobox.com>