1757 	gca = find_gca_candidates(self, revs, revcount);

  1758 	if (gca == NULL)

  1759 		goto bail;

  1760 

  1761 	if (PyList_GET_SIZE(gca) <= 1) {

  1762 		ret = gca;

  1763 		Py_INCREF(gca);

  1764 	}

  1765 	else ret = find_deepest(self, gca);

  1766 

  1767 done:

  1768 	free(revs);

  1769 	Py_XDECREF(gca);

  1770 

  1771 	return ret;

  1772 

  1773 bail:

  1774 	free(revs);

  1775 	Py_XDECREF(gca);

  1776 	Py_XDECREF(ret);

  1777 	return NULL;

  1778 }

  1779 

  1780 /*

  1781  * Given a (possibly overlapping) set of revs, return all the

  1782  * common ancestors heads: heads(::args[0] and ::a[1] and ...)

  1783  */

  1784 static PyObject *index_commonancestorsheads(indexObject *self, PyObject *args)

  1785 {

  1786 	PyObject *ret = NULL;

  1787 	Py_ssize_t argcount, i, len;

  1788 	bitmask repeat = 0;

  1789 	int revcount = 0;

  1790 	int *revs;

  1791 

  1792 	argcount = PySequence_Length(args);

  1793 	revs = malloc(argcount * sizeof(*revs));

  1794 	if (argcount > 0 && revs == NULL)

  1795 		return PyErr_NoMemory();

  1796 	len = index_length(self) - 1;

  1797 

  1798 	for (i = 0; i < argcount; i++) {

  1799 		static const int capacity = 24;

  1800 		PyObject *obj = PySequence_GetItem(args, i);

  1801 		bitmask x;

  1802 		long val;

  1803 

  1804 		if (!PyInt_Check(obj)) {

  1805 			PyErr_SetString(PyExc_TypeError,

  1806 					"arguments must all be ints");

  1807 			Py_DECREF(obj);

  1808 			goto bail;

  1809 		}

  1810 		val = PyInt_AsLong(obj);

  1811 		Py_DECREF(obj);

  1812 		if (val == -1) {

  1813 			ret = PyList_New(0);

  1814 			goto done;

  1815 		}

  1816 		if (val < 0 || val >= len) {

  1817 			PyErr_SetString(PyExc_IndexError,

  1818 					"index out of range");

  1819 			goto bail;

  1820 		}

  1821 		/* this cheesy bloom filter lets us avoid some more

  1822 		 * expensive duplicate checks in the common set-is-disjoint

  1823 		 * case */

  1824 		x = 1ull << (val & 0x3f);

  1825 		if (repeat & x) {

  1826 			int k;

  1827 			for (k = 0; k < revcount; k++) {

  1828 				if (val == revs[k])

  1829 					goto duplicate;

  1830 			}

  1831 		}

  1832 		else repeat |= x;

  1833 		if (revcount >= capacity) {

  1834 			PyErr_Format(PyExc_OverflowError,

  1835 				     "bitset size (%d) > capacity (%d)",

  1836 				     revcount, capacity);

  1837 			goto bail;

  1838 		}

  1839 		revs[revcount++] = (int)val;

  1840 	duplicate:;

  1841 	}

  1842 

  1843 	if (revcount == 0) {

  1844 		ret = PyList_New(0);

  1845 		goto done;

  1846 	}

  1847 	if (revcount == 1) {

  1848 		PyObject *obj;

  1849 		ret = PyList_New(1);

  1850 		if (ret == NULL)

  1851 			goto bail;

  1852 		obj = PyInt_FromLong(revs[0]);

  1853 		if (obj == NULL)

  1854 			goto bail;

  1855 		PyList_SET_ITEM(ret, 0, obj);

  1856 		goto done;

  1857 	}

  1858