I'm trying to configure a project with meson. Specifically, I'm trying to set some of the options.
meson config tells me, among other things:
Core options:
Option Current Value Possible Values Description
------ ------------- --------------- -----------
buildtype debug [plain, debug, debugoptimized, release, minsize, custom] Build type to use
Base options:
Option Current Value Possible Values Description
------ ------------- --------------- -----------
b_lto false [true, false] Use link time optimization
(other options were clipped from this printout of course.)
So, I write:
meson build . --buildtype=release
in my build directory, and this goes fine - no warnings or errors (I double-checked that the option value had changed). Then I write:
meson build . --b_lto=true
but this gets me:
meson: error: unrecognized arguments: --b_lto=true
I also tried -b_lto=true, --b_lto true, b_lto=true and b_lto true. And all of those without the true value. No luck.
How do I set these "base options" then?
The --option=value, and --option value styles to pass arguments only applies to the universial options section in meson's manual...so not to base options, and others. Instead use the -Doption=value syntax to set options. It is the suggested way, since meson setup --help declares [-D option] to be used for setting all sorts of options. See this answer by the meson team. So, in your case run:
meson build . -Db_lto=true
or
meson configure build -Db_lto=true
If the build directory changed since the last configure use reconfigure instead.
meson reconfigure build -Db_lto=true
or explicitly:
meson setup --reconfigure -Db_lto=true build