The first part of the patch fixes a (harmless?) compiler warning, whilst the second ensures that the debug macro will compile under MIPSpro (which requires all named arguments in a varadic macro to exist - so a call to x(i, j, k, ...) would need a minimum of three arguments - the 'k' value cannot be omitted, even though the compiler is C99 compliant).
Created attachment 207988 [details, diff] net-libs/libssh2 patch for IRIX/MIPSpro
patch added, thanks.