From a09cbea449850c679e27c83e4272bea399151996 Mon Sep 17 00:00:00 2001 From: Boris Kolpackov Date: Tue, 11 Jun 2024 14:44:11 +0200 Subject: Update NEWS file --- NEWS | 391 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 391 insertions(+) diff --git a/NEWS b/NEWS index 597156e..1c285c7 100644 --- a/NEWS +++ b/NEWS @@ -1,3 +1,394 @@ +Version 0.17.0 + + * C++20 modules support improvements: + + - Named modules support in Clang, including automatic building of the + `std` and `std.compat` standard library modules from libc++ with Clang + 18 or later. + + - Named modules support in MSVC, including automatic building of the `std` + and `std.compat` standard library modules. + + Note: if combining the standard library modules importation with the + standard library headers inclusion, MSVC 17.10 or later is recommended. + + - Modules support can now be enabled for any std.cxx value greater or + equal 20 (including `latest`). + + - The "C++ Modules Support" section in the manual has been updated to + match the current state of the implementation. + + * The `latest` and `experimental` cxx.std values are now mapped to C++26 + from GCC 14 and Clang 18. + + * The 23 and 2x c.std values are now mapped to /std:clatest starting from + MSVC 17.9. In particular, this option enables C23 typeof support. + + * /Zc:preprocessor is now added for the `experimental` cxx.std value from + MSVC 17.9. + + * New string_set buildfile value type. + + This exposes the std::set type to buildfiles. + + New functions: + + $size() + + Subscript returns true if the value is present and false otherwise (so + it is mapped to std::set::contains()). For example: + + set = [string_set] a b c + + if ($set[b]) + ... + + Note that append (+=) and prepend (=+) have the same semantics + (std::set::insert()). For example: + + set = [string_set] a b + set += c b # a b c + set =+ d b # a b c d + + Example of iteration: + + set = [string_set] a b c + for k: $set + ... + + * New string_map buildfile value type. + + This exposes the std::map type to buildfiles. + + New functions: + + $size() + $keys() + + Subscript can be used to look up a value by key. The result is [null] if + there is no value associated with the specified key. For example: + + map = [string_map] a@1 b@2 c@3 + + b = ($map[b]) # 2 + + if ($map[z] == [null]) + ... + + Note that append (+=) is overriding (like std::map::insert_or_assign()) + while prepend (=+) is not (like std::map::insert()). In a sense, whatever + appears last (from left to right) is kept, which is consistent with what + we expect to happen when specifying the same key repeatedly in a literal + representation. For example: + + map = [string_map] a@0 b@2 a@1 # a@1 b@2 + map += b@0 c@3 # a@1 b@0 c@3 + map =+ b@1 d@4 # a@1 b@0 c@3 d@4 + + Example of iteration: + + map = [string_map] a@1 b@2 c@3 + for p: $map + { + k = $first($p) + v = $second($p) + } + + While the subscript is mapped to key lookup only, index-based access can + be implemented (with a bit of overhead) using the $keys() function: + + map = [string_map] a@1 b@2 c@3 + keys = $keys($m) + for i: $integer_sequence(0, $size($keys)) + { + k = ($keys[$i]) + v = ($map[$k]) + } + + * New JSON buildfile value types. + + New types: + + json + json_array + json_object + + New functions: + + $json.value_type() + $json.value_size() + $json.member_{name,value}() + $json.object_names() + $json.array_size() + $json.array_find(, ) + $json.array_find_index(, ) + $json.load() + $json.parse() + $json.serialize([, ]) + + See "JSON Functions" in the manual for details. + + For example, to load a JSON value from a file: + + j = $json.load($src_base/board.json) + + Or to construct it in a buildfile: + + j = [json] one@1 two@([json] 2 3 4) three@([json] x@1 y@-1) + + This can also be done incrementally with append/prepend: + + j = [json_object] + j += one@1 + j += two@([json] 2 3 4) + j += three@([json] x@1 y@-1) + + Instead of using this JSON-like syntax, one can also specify valid JSON + input text: + + j = [json] '{"one":1, "two":[2, 3, 4], "three":{"x":1, "y":-1}' + + Besides the above set of functions, other handy ways to access components + in a JSON value are iteration and subscript. For example: + + for m: $j + print $member_name($m) $member_value($m) + + print ($j[three]) + + A subscript can be nested: + + print ($j[two][1]) + print ($j[three][x]) + + While a JSON value can be printed directly like any other value, the + representation will not be pretty-printed. As a result, for complex + JSON values, printing a serialized representation might be a more + readable option: + + info $serialize($j) + + * New json_map and json_set buildfile value types. + + These expose the std::map and std::set + types to buildfiles. + + New functions: + + $size() + $size() + $keys() + + Note that the $keys() function returns the list of map key as a json + array. + + For example: + + m = [json_map] 2@([json] a@1 b@2) 1@([json] 1 2) + s = [json_set] ([json] x@1 y@2) ([json] a@1 b@2) + + print ($m[2][b]) # 2 + print ($s[([json] y@2 x@1)]) # true + + * New $first() and $second() functions which return the first and second + halves of a pair, respectively. + + * New string functions: + + $string.contains() + $string.starts_with() + $string.ends_with() + $string.replace() + + See "String Functions" in the manual for details. + + * New path functions: + + $path.absolute() + $path.simple() + $path.sub_path() + $path.super_path() + $path.complete() + $path.try_normalize() + $path.try_actualize() + + See "Path Functions" in the manual for details. + + * New filesystem functions: + + $filesystem.file_exists() + $filesystem.directory_exists() + + See "Filesystem Functions" in the manual for details. + + * Runtime/buildtime distinction when installing libraries. + + Specifically, now, if a library is installed solely as a prerequisite of + an executable (potentially recursively), then only its runtime files are + installed omitting everything buildtime-related (static/import libraries, + non-versioned symlinks for shared libraries, pkg-config files, headers, + etc). If you are familiar with the runtime and -dev/-devel package splits + for libraries in Debian/Fedora, this is the analogous semantics. + + * Support for extracting C and C++ predefined macros (predefs). + + Specifically, the c and cxx modules now provide the c.predefs and + cxx.predefs submodules which can be loaded in order to register a rule + that generates a C or C++ header with the predefined compiler macros, + respectively. For details, refer to "C Compiler Predefined Macro + Extraction" and "C++ Compiler Predefined Macro Extraction" in the manual. + + * Ability to serialize compilation/linking in C/C++ rules. + + Specifically, both the C/C++ compile and link rules now recognize the + cc.serialize boolean variable which instructs them to compile/link + serially with regards to any other recipe. + + This is primarily useful when compiling large translation units or linking + large binaries that require so much memory that doing that in parallel + with other compilation/linking jobs is likely to summon the OOM killer. + For example: + + obj{memory-hog}: cc.serialize = true + + * Ability to specify compiler mode options in a buildfile. + + Now the configured mode options are appended to buildfile-specified (which + must be specified before loading the guess module). + + In particular, this ability to specify the compiler mode in a buildfile is + useful in embedded development where the project may need to hardcode + options like -target, -nostdinc, etc. For example: + + cxx.std = 20 + cxx.mode = -target riscv32-unknown-unknown -nostdinc + using cxx + + * New ~host-no-warnings and ~build2-no-warnings special configurations. + + These are parallel to ~host and ~build2 but with suppressed C/C++ compiler + warnings. + + Note also that the C++ ad hoc recipes are now by default built in + ~build2-no-warnings instead of ~build2 unless the project is configured + for development with config..develop=true. + + * New {bin,c,cxx}.types submodules that only register target types. + + This is primarily useful when providing custom C/C++ compilation/linking + rules. + + * New -s|--timeout-success option in the `env` script builtin. + + The semantics is equivalent to the --success option in the `timeout` + builtin. + + * Ability to specify alternative sysroot for pkg-config files. + + Specifically, the new config.cc.pkgconfig.sysroot variable provides + roughly equivalent functionality to PKG_CONFIG_SYSROOT_DIR in + pkg-config. For details and limitations, see "Rewriting Installed + Libraries System Root (sysroot)" in the manual for details. + + * Ability to alias a target type from another project. + + The syntax is: + + define = / + + For example: + + sdk_proj = ... # Root directory of the SDK. + define ldscript = $sdk_proj/ldscript + + + Additionally, unknown target types of imported targets are now aliased + automatically. + + * New no_default_target attribute for source, buildfile import directives. + + This attribute can be used to disable the default target semantics for the + sources/imported buildfile. + + * Allow imported buildfiles to use config.* variables from own projects + (that is, the project from which the buildfile is imported). + + * The fsdir{} targets are now usable in ad hoc recipes. + + In particular, they can now be used to represent directory symlinks. For + example: + + exe{hello}: ... fsdir{assets} + + fsdir{assets}: + % update + {{ + ln -s $src_base/assets $out_base/assets + }} + % clean + {{ + rm $out_base/assets + }} + + Likewise, file{} targets can now be used to represent file symlinks + created in ad hoc recipes. + + * Ability to specify ad hoc recipes in separate files. + + This can now be achieved with the new `recipe` directive: + + recipe + + Note that similar to the use of if-else and switch directives with recipes, + this directive requires explicit % recipe header. For example, instead of: + + file{foo.output}: + {{ + echo 'hello' >$path($>) + }} + + We can now write: + + file{foo.output}: + % + recipe buildscript hello.buildscript + + With hello.buildscript containing: + + echo 'hello' >$path($>) + + Similarly, for C++ recipes (this time for a pattern rule), instead of: + + [rule_name=hello] file{~'/(.+)\.output/'}: + % update clean + {{ c++ 1 -- + + -- + + ... + + }} + + We can now write: + + [rule_name=hello] file{~'/(.+)\.output/'}: + % update clean + recipe c++ hello.cxx + + With hello.cxx containing: + + // c++ 1 -- + + -- + + ... + + Relative paths are resolved using the buildfile directory that + contains the `recipe` directive as a base. + + Note also that this mechanism can be used in exported buildfiles with + recipe files placed into build/export/ together with buildfiles. + Version 0.16.0 * Support for Objective-C/C++ compilation. -- cgit v1.1