Mercurial > cpython-lru_cache-weakref
diff Python/compile.c @ 44865:8103f0198967 2.5
Issue 1678380: fix a bug identifying -0.0 and 0.0
| author | Mark Dickinson <dickinsm@gmail.com> |
|---|---|
| date | Mon, 21 Jan 2008 21:54:47 +0000 |
| parents | 692493771ae3 |
| children | 742a264cce4f |
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--- a/Python/compile.c Mon Jan 21 18:36:54 2008 +0000 +++ b/Python/compile.c Mon Jan 21 21:54:47 2008 +0000 @@ -1567,7 +1567,20 @@ Py_ssize_t arg; /* necessary to make sure types aren't coerced (e.g., int and long) */ - t = PyTuple_Pack(2, o, o->ob_type); + /* _and_ to distinguish 0.0 from -0.0 e.g. on IEEE platforms */ + if (PyFloat_Check(o)) { + double d = PyFloat_AS_DOUBLE(o); + unsigned char* p = (unsigned char*) &d; + /* all we need is to make the tuple different in either the 0.0 + * or -0.0 case from all others, just to avoid the "coercion". + */ + if (*p==0 && p[sizeof(double)-1]==0) + t = PyTuple_Pack(3, o, o->ob_type, Py_None); + else + t = PyTuple_Pack(2, o, o->ob_type); + } else { + t = PyTuple_Pack(2, o, o->ob_type); + } if (t == NULL) return -1;
