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@@ -1055,6 +1055,19 @@ are listed below.
the behavior of sanitizers in the ``cfi`` group to allow checking
of cross-DSO virtual and indirect calls.
+.. option:: -ffast-math
+
+ Enable fast-math mode. This defines the ``__FAST_MATH__`` preprocessor
+ macro, and lets the compiler make aggressive, potentially-lossy assumptions
+ about floating-point math. These include:
+
+ * Floating-point math obeys regular algebraic rules for real numbers (e.g.
+ ``+`` and ``*`` are associative, ``x/y == x * (1/y)``, and
+ ``(a + b) * c == a * c + b * c``),
+ * operands to floating-point operations are not equal to ``NaN`` and
+ ``Inf``, and
+ * ``+0`` and ``-0`` are interchangeable.
+
.. option:: -fwhole-program-vtables
Enable whole-program vtable optimizations, such as single-implementation