Bruno Haible <bruno@xxxxxxxxx> writes: > 'expr' is certainly the easiest auxiliary program that can be used to > compute "2*x" and "(x+y)/2" for some integers x and y, but it's not the > only one. You could also use 'sed' for this purpose. Oh my goodness, I hadn't thought of that! But I'd rather not program extended-precision arithmetic by hand with 'sed'. Instead, I was thinking of fixing _AC_COMPUTE_INT to handle integers outside the range LONG_MIN..LONG_MAX by having the shell use simple string concatenation, and having the C compiler do the arithmetic instead. If size_t is 32-bit 'unsigned long', for example, it suffices for config.h to contain this: #define SIZE_MAX (2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(2*(1ul)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1)+1) and expressions like these can be computed easily using binary search.
