Hello All, I discovered a rather obscure set of compiler flags -Wshadow, -Wshadow=local, -Wshadow=compatible-local while trying to track down a bug which warn about local redefinition of a variable. Out of curiosity I also recompiled petsc with this flag and lo and behold the src is littered with shadowed variables. From what I can tell most are likely harmless — defining an iterator variable in the beginning of the function with all the rest of the variables, then redefining it later in some loop — but maybe we should consider adding this as a CI flag as it isn’t activated by -Wall. Best regards, Jacob Faibussowitsch (Jacob Fai - booss - oh - vitch) Cell: (312) 694-3391