Install solidity meet the problem--unused variable ' returned '

In the process of compiling and installing solidity, I met a strange problem.

Webthree-umbrella/libethereum/libethereum/executive.CPP: in memberfunction 'void Dev::eth::standardtrace::operator () (uint64_t, uint64_t, Dev::eth::instruction, Dev::bigint, Dev::bigint, Dev::bigint, dev::eth::vm*, const dev::eth::extvmface*)':/home/vagrant/code/workspace/webthree-umbrella/libethereum/libethereum/executive.CPP: 81:8: error:unused Variable'returned'[-werror=unused-variable]BOOLreturned =true;^Cc1plus:all warnings being treated as errors

It seems to be that the process of compiling a warning as an error is handled. The variable "returned" is then defined but not used, causing a warning to be treated as an error.

But looking at the compile option doesn't seem to be a "-werror=unused-variable" option, so you can't have to webthree-umbrella/libethereum/libethereum/ Executive.cpp in this file, it is found that a returned variable is defined, and only one assignment is done at a time, and the other places are completely useless.

Just comment out the two statements of the returned declaration and assignment.

Then recompile, success!

Test:

Enter the webthree-umbrella/build/solidity/solc/directory with the file Solc executable program

Just run this, okay?

Install solidity meet the problem--unused variable ' returned '