Support for MSYS2 / MinGW64

[plicease]

MSYS2 / MinGW64 has .pc files that are relative to the MinGW64 root.

Strawberry Perl

> pkg-config.bat --with-path=C:\msys64\mingw64\lib\pkgconfig --cflags gtk+-3.0
-I/mingw64/include/gtk-3.0 -mms-bitfields -I/mingw64/include/pango-1.0 -I/mingw64/include/glib-2.0 -I/mingw64/lib/glib-2.0/include -I/mingw64/include/cairo -I/mingw64/include/gdk-pixbuf-2.0 -I/mingw64/include/atk-1.0

MSYS2 / MinGW64 shell

$ pkg-config --cflags gtk+-3.0
-mms-bitfields -pthread -mms-bitfields -IC:/msys64/mingw64/include/gtk-3.0 -IC:/msys64/mingw64/include/cairo -IC:/msys64/mingw64/include -IC:/msys64/mingw64/include/pango-1.0 -IC:/msys64/mingw64/include/atk-1.0 -IC:/msys64/mingw64/include/cairo -IC:/msys64/mingw64/include/pixman-1 -IC:/msys64/mingw64/include -I/mingw64/include/freetype2 -I/mingw64/include/libpng16 -I/mingw64/include/harfbuzz -I/mingw64/include/glib-2.0 -I/mingw64/lib/glib-2.0/include -IC:/msys64/mingw64/include -IC:/msys64/mingw64/include/freetype2 -IC:/msys64/mingw64/include -IC:/msys64/mingw64/include/harfbuzz -IC:/msys64/mingw64/include/libpng16 -IC:/msys64/mingw64/include/gdk-pixbuf-2.0 -IC:/msys64/mingw64/include/libpng16 -IC:/msys64/mingw64/include/glib-2.0 -IC:/msys64/mingw64/lib/glib-2.0/include

[plicease]

/cc: @sivoais

[zmughal]

The path problem can be fixed with cygpath which is part of MSYS2 (extended from the Cygwin equivalent).

On my system:

convert-flags-with-cygpath.pl

#!perl

use strict;
use warnings;

use Text::ParseWords;
use v5.016;

my @flags = shellwords(<>);
say( join $/,
    map {
        if( my ($type, $path) = $_ =~ /^(-[IL])(.*)$/ ) {
            my $win_path = qx(C:/msys64/usr/bin/cygpath -w $path);
            chomp $win_path;
            "$type$win_path";
        } else {
            $_;
        }
    } @flags );

> pkg-config.bat --with-path=C:\msys64\mingw64\lib\pkgconfig --cflags gtk+-3.0

-I/mingw64/include/gtk-3.0 -mms-bitfields -I/mingw64/include/pango-1.0 -I/mingw64/include/glib-2.0 -I/mingw64/lib/glib-2.0/include -I/mingw64/include/cairo -I/mingw64/include/gdk-pixbuf-2.0 -I/mingw64/include/atk-1.0

> pkg-config.bat --with-path=C:\msys64\mingw64\lib\pkgconfig --cflags gtk+-3.0 | perl convert-flags-with-cygpath.pl

-IC:\msys64\mingw64\include\gtk-3.0
-mms-bitfields
-IC:\msys64\mingw64\include\pango-1.0
-IC:\msys64\mingw64\include\glib-2.0
-IC:\msys64\mingw64\lib\glib-2.0\include
-IC:\msys64\mingw64\include\cairo
-IC:\msys64\mingw64\include\gdk-pixbuf-2.0
-IC:\msys64\mingw64\include\atk-1.0

[plicease]

Another difference is that MSYS2 pkg-config seems to default to --static

ollisg@donut MSYS /d/home/ollisg/dev/PkgConfig
$ pkg-config libarchive --libs
-larchive -lnettle -llzo2 -llzma -lbz2 -lz -lxml2 -lz -lpthread -liconv -lm

ollisg@donut MSYS /d/home/ollisg/dev/PkgConfig
$ perl lib/PkgConfig.pm  libarchive --libs
-larchive

ollisg@donut MSYS /d/home/ollisg/dev/PkgConfig
$ perl lib/PkgConfig.pm  --static libarchive --libs
-larchive -lnettle -llzo2 -llzma -lbz2 -lz -lxml2 -lpthread -liconv -lm

update: this seems intentional. --enable-indirect-deps is passed into ./configure:

build() {
  cd ${srcdir}/${pkgname}-${pkgver}
  ./configure \
    --build=${CHOST} \
    --host=${CHOST} \
    --prefix=/usr \
    --with-internal-glib \
    --enable-indirect-deps
  make
}

[plicease]

32d2ba5

[plicease]

MSYS2 has a default search path as mentioned in 32d2ba5 .
MSYS2 also sets PKG_CONFIG_PATH so if you want the correct search path from outside of MSYS2 for stuff inside MSYS2 you need to know this:

Adding directory '/usr/lib/pkgconfig' from PKG_CONFIG_PATH
Adding directory '/usr/share/pkgconfig' from PKG_CONFIG_PATH
Adding directory '/lib/pkgconfig' from PKG_CONFIG_PATH
Adding directory '/usr/lib/pkgconfig' from PKG_CONFIG_PATH
Adding directory '/usr/share/pkgconfig' from PKG_CONFIG_PATH

[zmughal]

It might be useful to note that the search path $PKG_CONFIG_PATH is different depending on which shell you open:

MSYS2: /usr/lib/pkgconfig:/usr/share/pkgconfig:/lib/pkgconfig

MINGW32: /mingw32/lib/pkgconfig:/mingw32/share/pkgconfig

MINGW64: /mingw64/lib/pkgconfig:/mingw64/share/pkgconfig

The reason is that you don't really want to compile against the MSYS2 environment. A good description pulled from the MSYS2 documentation is:

MSYS2 consists of three subsystems and their corresponding package repositories, msys2, mingw32, and mingw64.

The mingw subsystems provide native Windows programs and are the main focus of the project. These programs are built to co-operate well with other Windows programs, independently of the other subsystems.

The msys2 subsystem provides an emulated mostly-POSIX-compliant environment for building software, package management, and shell scripting. These programs live in a virtual single-root filesystem (the root is the MSYS2 installation directory). Some effort is made to have the programs work well with native Windows programs, but it's not seamless.

Each of the subsystems provides its own native (i.e. target=host) compiler toolchain, in msys2-devel, mingw-w64-i686-toolchain, and mingw-w64-x86_64-toolchain. There are also cross compiler toolchains with host={i686,x86_64}-pc-msys and target={i686,x86_64}-w64-mingw32 in mingw-w64-cross-toolchain, but these are of limited use because there are no library packages for them.

Every subsystem has an associated "shell", which is essentially a set of environment variables that allow the subsystems to co-operate properly. These shells can be invoked using scripts in the MSYS2 installation directory or shortcuts in the Start menu. The scripts set the MSYSTEM variable and start a terminal emulator with bash. Bash in turn sources /etc/profile which sets the environment depending on the value of MSYSTEM.

[plicease]

@zmughal Good background! It makes more sense now. When running PkgConfig.pm with MSYS2 Perl, you should get the same search path with or without the environment variable now.