G_MODULE_SUFFIX is deprecated now because you will get the wrong
results using it most of the time:
1. The suffix on macOS is usually 'dylib', but it's 'so' when using
Autotools, so there's no way to get the suffix correct using
a pre-processor macro.
2. Prefixes also vary in a platform-specific way. You may or may not have
a 'lib' prefix for the name on Windows and on Cygwin the prefix is
'cyg'.
3. The library name itself can vary per platform. For instance, you may
want to load foo-1.dll on Windows and libfoo.1.dylib on macOS. This
is for libraries, not modules, but that is still a use-case that
people use the GModule API for.
g_module_build_path() does take care of (2) on Cygwin, but it
fundamentally cannot handle the possibility of multiple options for
the module name, since it does not do any I/O. Hence, it is also
deprecated.
Instead, g_module_open() has been improved so that it takes care of
all this by searching the filesystem for combinations of possible
suffixes and prefixes on each platform. Along the way, the
documentation for it was also improved to make it clearer what it
does.
Closes https://gitlab.gnome.org/GNOME/glib/-/issues/520
Closes https://gitlab.gnome.org/GNOME/glib/-/issues/1413
The plugin modules in these tests get statically linked with a separate
copy of GLib so they end up calling vfuncs in their own copy of GLib.
Fixes#1648
On Visual Studio, Meson builds modules as xxxx.dll, not libxxxx.dll when
xxxx is specified as the name for the shared_module() build directive.
This means that in the test programs if we expect for libxxxx for the
module name, the test will fail as there is no libxxxx.dll but there is
xxxx.dll. This makes the test program look for the module files
correctly.
The file extension of the GIO module could be something other than .so,
depending on platform. Use G_MODULE_SUFFIX so that the test will run
correctly on non-*nix platforms, such as Windows.
https://bugzilla.gnome.org/show_bug.cgi?id=719344