[Bug c++/33515] New: Inconsistent warning about "defined but not used"

["mec at google dot com" <gcc-bugzilla at gcc dot gnu dot org>]

Consider this code:

  class Alpha { public: Alpha(); };
  static Alpha* a1 = new Alpha;

Should this draw a warning about a1 defined-but-not-used?  gcc 4.3-20070914
gives a warning on some programs but not others.  Specifically, I see the
warning if a program has an unrelated syntax error.  This is odd.

 mec@hollerith:~/exp-defined$ cat z2.cc
class Alpha {
  public:
    Alpha();
    ~Alpha();
  private:
    int i;
};

static Alpha* a1 = new Alpha;

int Beta() {
  return 0;
}

mec@hollerith:~/exp-defined$ /home/mec/gcc-4.3-20070914/install/bin/g++ -Wall
-S z2.cc
mec@hollerith:~/exp-defined$ cat z3.cc
class Alpha {
  public:
    Alpha();
    ~Alpha();
  private:
    int i;
};

static Alpha* a1 = new Alpha;

int Beta() {
  return x;
}

mec@hollerith:~/exp-defined$ /home/mec/gcc-4.3-20070914/install/bin/g++ -Wall
-S z3.cc
z3.cc: In function 'int Beta()':
z3.cc:12: error: 'x' was not declared in this scope
z3.cc: At global scope:
z3.cc:9: warning: 'a1' defined but not used

mec@hollerith:~/exp-defined$


-- 
           Summary: Inconsistent warning about "defined but not used"
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: mec at google dot com
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33515