predigit, nines = 0;

-- Mac OS X, Apple LLVM version 7.3.0 (clang-703.0.31)

demo.c:41:13: warning: expression result unused [-Wunused-value]
            predigit, nines = 0;
            ^~~~~~~~
1 warning generated.

03141592653589793238462643383279542884197169399375105820974944592307816406286208998628734825342117067
                                 |                                                    |
                                 4                                                    7

-- Linux, gcc version 4.8.5 20150623

03141592653589793238462643383279542884197169399375105820974944592307816406286208998628734825342117067
                                 |                                                    |
                                 4                                                    7


##</code><code>##

predigit = 0, nines = 0;

03141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067
                                 |                                                    |
                                 0                                                    0