// Copyright David Abrahams 2002. Permission to copy, use, // modify, sell and distribute this software is granted provided this // copyright notice appears in all copies. This software is provided // "as is" without express or implied warranty, and with no claim as // to its suitability for any purpose. #ifndef WORKAROUND_DWA2002126_HPP # define WORKAROUND_DWA2002126_HPP // Compiler/library version workaround macro // // Usage: // // #if BOOST_WORKAROUND(BOOST_MSVC, <= 1200) // ... // workaround code here // #endif // // When BOOST_STRICT_CONFIG is defined, expands to 0. Otherwise, the // first argument must be undefined or expand to a numeric // value. The above expands to: // // (BOOST_MSVC) != 0 && (BOOST_MSVC) <= 1200 // // When used for workarounds on the latest known version of a // compiler, the following convention should be observed: // // #if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1301)) // // The version number in this case corresponds to the last version in // which the workaround was known to have been required. It only has // value as a comment unless BOOST_DETECT_OUTDATED_WORKAROUNDS is // defined, in which case a compiler warning or error will be issued // when the compiler version exceeds the argument to BOOST_CHECKED_AT # ifndef BOOST_STRICT_CONFIG # define BOOST_WORKAROUND(symbol, test) \ (symbol != 0) && (1 % (( (symbol test) ) + 1)) // ^ ^ ^ ^ // The extra level of parenthesis nesting above, along with the // BOOST_OPEN_PAREN indirection below, is required to satisfy the // broken preprocessor in MWCW 8.3 and earlier. // // The basic mechanism works as follows: // (symbol test) + 1 => 2 if the test passes, 1 otherwise // 1 % ((symbol test) + 1) => 1 if the test passes, 0 otherwise // // The complication with % is for cooperation with BOOST_TESTED_AT(). // When "test" is BOOST_TESTED_AT(x) and // BOOST_DETECT_OUTDATED_WORKAROUNDS is #defined, // // symbol test => 1 if symbol <= x, -1 otherwise // (symbol test) + 1 => 2 if symbol <= x, 0 otherwise // 1 % ((symbol test) + 1) => 1 if symbol <= x, zero divide otherwise // # ifdef BOOST_DETECT_OUTDATED_WORKAROUNDS # define BOOST_OPEN_PAREN ( # define BOOST_TESTED_AT(value) > value) ?(-1): BOOST_OPEN_PAREN 1 # else # define BOOST_TESTED_AT(value) != 0 # endif # else # define BOOST_WORKAROUND(symbol, test) 0 # endif #endif // WORKAROUND_DWA2002126_HPP