foo.cc:2:24: error: extended character “ is not valid in an identifier
    2 | #pragma GCC optimize(3,“Ofast”,“inline”)
      |                        ^
foo.cc:2:24: error: extended character ” is not valid in an identifier
foo.cc:2:32: error: extended character “ is not valid in an identifier
    2 | #pragma GCC optimize(3,“Ofast”,“inline”)
      |                                ^
foo.cc:2:32: error: extended character ” is not valid in an identifier
foo.cc:2:24: warning: '#pragma GCC optimize (string [,string]...)' does not have a final ')' [-Wpragmas]
    2 | #pragma GCC optimize(3,“Ofast”,“inline”)
      |                        ^~~~~~~

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