diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e6038259986830db2a3e178e774d5f69365ff505..d2c7c64e2542e701c0d118b5c9842bd0656782bd 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2004-06-15  Paolo Bonzini  <bonzini@gnu.org>
+
+	* fold-const.c (operand_equal_p): Update comment.
+
 2004-06-15  Kazuhiro Inaoka  <inaoka.kazuhiro@renesas.com>
 
 	* config/m32r/m32r.h (RETURN_ADDR_RTX): Define.
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 1cc2b8189c880954d4eab18a940df201cf51b2f3..3c5a81d7253dea41d0da1d77d7edc3eb5805ee2b 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -2337,10 +2337,10 @@ truth_value_p (enum tree_code code)
    executed between the evaluation of its "operands" (which may often
    be evaluated in arbitrary order).  Hence if the operands themselves
    don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
-   same value in each operand/subexpression.  Hence a zero value for
-   ONLY_CONST assumes isochronic (or instantaneous) tree equivalence.
-   If comparing arbitrary expression trees, such as from different
-   statements, ONLY_CONST must usually be nonzero.
+   same value in each operand/subexpression.  Hence leaving OEP_ONLY_CONST
+   unset means assuming isochronic (or instantaneous) tree equivalence.
+   Unless comparing arbitrary expression trees, such as from different
+   statements, this flag can usually be left unset.
 
    If OEP_PURE_SAME is set, then pure functions with identical arguments
    are considered the same.  It is used when the caller has other ways