predef/other/workaround.h

0001 /*
0002 Copyright Rene Rivera 2017
0003 Distributed under the Boost Software License, Version 1.0.
0004 (See accompanying file LICENSE_1_0.txt or copy at
0005 http://www.boost.org/LICENSE_1_0.txt)
0006 */
0007
0008 #ifndef BOOST_PREDEF_WORKAROUND_H
0009 #define BOOST_PREDEF_WORKAROUND_H
0010
0011 /* tag::reference[]
0012
0013 = `BOOST_PREDEF_WORKAROUND`
0014
0015 [source]
0016 ----
0017 BOOST_PREDEF_WORKAROUND(symbol,comp,major,minor,patch)
0018 ----
0019
0020 Usage:
0021
0022 [source]
0023 ----
0024 #if BOOST_PREDEF_WORKAROUND(BOOST_COMP_CLANG,<,3,0,0)
0025     // Workaround for old clang compilers..
0026 #endif
0027 ----
0028
0029 Defines a comparison against two version numbers that depends on the definion
0030 of `BOOST_STRICT_CONFIG`. When `BOOST_STRICT_CONFIG` is defined this will expand
0031 to a value convertible to `false`. Which has the effect of disabling all code
0032 conditionally guarded by `BOOST_PREDEF_WORKAROUND`. When `BOOST_STRICT_CONFIG`
0033 is undefine this expand to test the given `symbol` version value with the
0034 `comp` comparison against `BOOST_VERSION_NUMBER(major,minor,patch)`.
0035
0036 */ // end::reference[]
0037 #ifdef BOOST_STRICT_CONFIG
0038 #   define BOOST_PREDEF_WORKAROUND(symbol, comp, major, minor, patch) (0)
0039 #else
0040 #   include <boost/predef/version_number.h>
0041 #   define BOOST_PREDEF_WORKAROUND(symbol, comp, major, minor, patch) \
0042         ( (symbol) != (0) ) && \
0043         ( (symbol) comp (BOOST_VERSION_NUMBER( (major) , (minor) , (patch) )) )
0044 #endif
0045
0046 /* tag::reference[]
0047
0048 = `BOOST_PREDEF_TESTED_AT`
0049
0050 [source]
0051 ----
0052 BOOST_PREDEF_TESTED_AT(symbol,major,minor,patch)
0053 ----
0054
0055 Usage:
0056
0057 [source]
0058 ----
0059 #if BOOST_PREDEF_TESTED_AT(BOOST_COMP_CLANG,3,5,0)
0060     // Needed for clang, and last checked for 3.5.0.
0061 #endif
0062 ----
0063
0064 Defines a comparison against two version numbers that depends on the definion
0065 of `BOOST_STRICT_CONFIG` and `BOOST_DETECT_OUTDATED_WORKAROUNDS`.
0066 When `BOOST_STRICT_CONFIG` is defined this will expand to a value convertible
0067 to `false`. Which has the effect of disabling all code
0068 conditionally guarded by `BOOST_PREDEF_TESTED_AT`. When `BOOST_STRICT_CONFIG`
0069 is undefined this expand to either:
0070
0071 * A value convertible to `true` when `BOOST_DETECT_OUTDATED_WORKAROUNDS` is not
0072   defined.
0073 * A value convertible `true` when the expansion of
0074   `BOOST_PREDEF_WORKAROUND(symbol, <=, major, minor, patch)` is `true` and
0075   `BOOST_DETECT_OUTDATED_WORKAROUNDS` is defined.
0076 * A compile error when the expansion of
0077   `BOOST_PREDEF_WORKAROUND(symbol, >, major, minor, patch)` is true and
0078   `BOOST_DETECT_OUTDATED_WORKAROUNDS` is defined.
0079
0080 */ // end::reference[]
0081 #ifdef BOOST_STRICT_CONFIG
0082 #   define BOOST_PREDEF_TESTED_AT(symbol, major, minor, patch) (0)
0083 #else
0084 #   ifdef BOOST_DETECT_OUTDATED_WORKAROUNDS
0085 #       define BOOST_PREDEF_TESTED_AT(symbol, major, minor, patch) ( \
0086             BOOST_PREDEF_WORKAROUND(symbol, <=, major, minor, patch) \
0087             ? 1 \
0088             : (1%0) )
0089 #   else
0090 #       define BOOST_PREDEF_TESTED_AT(symbol, major, minor, patch) \
0091             ( (symbol) >= BOOST_VERSION_NUMBER_AVAILABLE )
0092 #   endif
0093 #endif
0094
0095 #endif