isnonalpha        170 third_party/libpng/pngerror.c       if (isnonalpha(c))
isnonalpha       2495 third_party/libpng/pngrutil.c    if (isnonalpha(chunk_name[0]) || isnonalpha(chunk_name[1]) ||
isnonalpha       2496 third_party/libpng/pngrutil.c        isnonalpha(chunk_name[2]) || isnonalpha(chunk_name[3]))