4.19 How the compiler handles bit-band objects placed outside bit-band regions

Bit-band objects must not be placed outside bit-band regions.

If you do inadvertently place a bit-band object outside a bit-band region, either using the at attribute, or using an integer pointer to a particular address, the compiler responds as follows:

  • If the bitband attribute is applied to an object type and --bitband is not specified on the command line, the compiler generates an error.

  • If the bitband attribute is applied to an object type and --bitband is specified on the command line, the compiler generates a warning, and ignores the request to bit-band.

  • If the bitband attribute is not applied to an object type and --bitband is specified on the command line, the compiler ignores the request to bit-band.

Related concepts
4.16 Compiler and processor support for bit-banding
4.17 Compiler type attribute, __attribute__((bitband))
4.18 --bitband compiler command-line option
Related reference
10.55 __attribute__((bitband)) type attribute
10.61 __attribute__((at(address))) variable attribute
8.17 --bitband
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