Specifications

CAVR-4
Part 2. Compiler reference
Pragma directives
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#pragma bitfields #pragma bitfields={reversed|default}
The #pragma bitfields directive controls the order of bitfield members.
By default, the AVR IAR C/C++ Compiler places bitfield members from the least
significant bit to the most significant bit in the container type. Use the
#pragma bitfields=reversed directive to place the bitfield members from the
most significant to the least significant bit. This setting remains active until you turn it
off again with the #pragma bitfields=default directive.
#pragma constseg
The #pragma constseg directive places constant variables in a named segment. Use
the following syntax:
#pragma constseg=MY_CONSTANTS
const int factorySettings[] = {42, 15, -128, 0};
#pragma constseg=default
The segment name cannot be a predefined segment; see the chapter Segment reference
for more information.
The memory in which the segment resides is optionally specified using the following
syntax:
#pragma constseg=__huge MyOtherSeg
All constants defined following this directive will be placed in the segment
MyOtherSeg and accessed using huge addressing.
#pragma data_alignment #pragma data_alignment=expression
Use this pragma directive to give a variable a higher (more strict) alignment than it
would otherwise have. It can be used on variables with static and automatic storage
duration.
The value of the constant expression must be a power of two (1, 2, 4, etc.).
When you use
#pragma data_alignment on variables with automatic storage
duration, there is an upper limit on the allowed alignment for each function, determined
by the calling convention used.
#pragma dataseg
The #pragma dataseg directive places variables in a named segment. Use the
following syntax:
#pragma dataseg=MY_SEGMENT
__no_init char myBuffer[1000];
#pragma dataseg=default