Suppressing C++ static analyzer in external C++ code?

I am including the glm library in my Xcode project and want to suppress this warning:

/opt/extlibs/macosx/include/glm/./ext/../gtc/bitfield.inl:343:15: warning: Although the value stored to 'x' is used in the enclosing expression, the value is never actually read from 'x' [deadcode.DeadStores]
                uint16 REG2(x >>= 1);
                            ^     ~

Is there a way to do that via a #pragma or a #define or something else in the Build Settings?