Compiling with GCC 9.2.1 I'm not able to generate a compile time warning with the following compiler flags removed. I wanted to see whether CI has any issues with the following removed. If any problems arise I'll take a look and possibly close this PR, otherwise perhaps we want to remove these flags to prevent the reintroduction of register, self assign or unused local typedef.
no-self-assign
no-unused-local-typedef
no-deprecated-register
The latest version of GCC isn't the only compiler we need to suppress warnings for. I'm still seeing at least -Wself-assign warnings on macOS with the latest Apple Clang:
Apple clang version 11.0.0 (clang-1100.0.33.17)
...
test/uint256_tests.cpp:272:7: warning: explicitly assigning value of variable of type 'arith_uint256' to itself [-Wself-assign-overloaded]
v /= v;
~ ^ ~
test/uint256_tests.cpp:276:7: warning: explicitly assigning value of variable of type 'arith_uint256' to itself [-Wself-assign-overloaded]
v -= v;
~ ^ ~
2 warnings generated.