4.6.5. The --fpmode option

You can specify the floating-point conformance and floating-point optimization using the --fpmode option. Different libraries are selected depending on the model chosen.

Table 4.12. Floating-point models supported in RVCT


--fpmode ieee_full

All facilities, operations and representations guaranteed by the IEEE standard are available in single and double precision. Modes of operation can be selected dynamically at run-time.

--fpmode ieee_fixed

IEEE standard with round-to-nearest and no inexact exceptions.

--fpmode ieee_no_fenv

IEEE standard with round-to-nearest and no exceptions. This mode is compatible with the Java floating-point arithmetic model.

--fpmode std

IEEE finite values with denormals flushed to zero, round-to-nearest and no exceptions. This is the default option and is C and C++ compatible.

--fpmode fast

Perform more aggressive floating-point optimizations that might cause a small loss of accuracy to provide a significant performance increase. This option results in behavior that is not fully compliant with the ISO C and ISO C++ standards. However, numerically robust floating-point programs behave correctly.


Initialization code might be required to enable the VFP. See VFP support for more information.

For more information on specifying floating-point conformance, see:

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