This was a missing feature that I had skipped previously.
Before this commit, each layer would overwrite all previous environment variables if they had anything defined.
After this commit, the layers will now merge in priority order.
Meaning if a higher priority layer has the same environment variable defined, it will overwrite that specific variable
Ending up with a superset of all the layer's environment variables now.
Leafs come from ECX but only some CPUID functions support this.
This adds the initial infrastructure but doesn't yet add support for the CPUID functions to consume the leaf.
This takes the changes from #829 and moves it to the correct location to be picked up from any loader.
This also fixes#873.
Expands the config paths. Anything that has ~ or is relative will be converted to an absolute path.
Ubuntu's x86_64 rootfs does a soft link from `/lib64/ld-linux-x86-64.so.2` to an absolute path of `/lib/x86_64-linux-gnu/ld-2.32.so`
Our frontend ELF loader logic would resolve this symlink to be just `/lib/x86_64-linux-gnu/ld-2.32.so` which would then fail.
Adds some additional logic to our frontend that if the symlink ends up being a softlink to an absolute address then it'll first resolve that symlink.
Then combines rootfs + absolute path. If that still fails then it'll fall down the regular linker path, which could still find the linker on the host side.
This is all a bit of a kludge to just work around Ubuntu doing an absolute address rather than a relative one.
Fixes#869
ARMv8 allows you query the cycle counter register very from userspace which allows us to emulate this easily.
My IceLake device returns 1.5Ghz through this interface
My AMD Zen+ device doesn't support this but with measurements has 3Ghz TSC
My Snapdragon 865 device has a TSC frequency of 19.20Mhz
va_list types have an edge where after operating on it, then it is undefined behaviour to do anything other than va_end on the object.
So in order to call vsnprintf on it multiple times we must create copies with va_copy.
Easy enough to work around by doing a few more copies of the va_list
This way we don't need to redeclare the arguments twice
Also moves IWYU lower so it doesn't hit any external projects other than FEXCore
Still not running these since everything needs to be cleaned up anyway
Passes the result back up to the frontend as well which allows us to early exit correctly.
Also ensures that we return ENOEXEC on these error cases so if someone is waiting on a return value, they don't just get zero
Fixes#757
Ryan Houdek