**System Information**
Operating system: Gentoo Linux
Graphics card: GeForce GTX 970M
**Blender Version**
Broken: 3.0.0
Worked: 2.93
The build system for Blender on Gentoo is configured to throw and error on any typecast which could potentially loose information. The get_progress() method is defined to return a double, but is used with float returns in cycles_standalone.cpp. This causes the compilation to terminate. The simple fix is to change the two instances of the get_process calls to return doubles, or alternatively change the get_progress to return a float.
This bug has been reported to the Blender Gentoo build manager (see: https://bugs.gentoo.org/830355 ) with workaround patch supplied (see: https://830355.bugs.gentoo.org/attachment.cgi?id=760945 )
**Exact steps for others to reproduce the error**
Build blender-3.0.0 with -Werror=return-type compiler flag set if compiling with a g++-11.2.0 compiler.