25.3.5 The Number of Significant Initial Characters in an Identifier

At least the first 255 characters in an identifier (internal and external) are significant. This extends upon the requirement of the C Language Standard, which states a lower number of significant characters are used to identify an object.

Example

The following example shows two poorly named variables, but names that are considered unique under the CCI.

int stateOfPortBWhenTheOperatorHasSelectedAutomaticModeAndMotorIsRunningFast;

int stateOfPortBWhenTheOperatorHasSelectedAutomaticModeAndMotorIsRunningSlow;

Differences

When using MPLAB XC8 for PIC targets and in C90 mode, only 31 significant characters have been accepted by default, but an option allowed this to be extended. When building in C99 mode for these devices, there has been no limit on the number of significant characters. There has also been no character limit when using MPLAB XC8 to target AVR MCUs, or when using any other compiler.

Migration to the CCI

No action required. You can take advantage of the less restrictive naming scheme.