Vault 7: Projects

This publication series is about specific projects related to the Vault 7 main publication.

Supported Data Types and Variables
2012-2013 Microchip Technology Inc. DS50002071C-page 133
This attribute is useful for writing code that is portable across all supported compiler tar-
gets. For example, the following function adds two 32-bit signed integers and returns a
32-bit signed integer result:
typedef int __attribute__((__mode__(SI))) int32;
int32
add32(int32 a, int32 b)
{
return(a+b);
}
You may also specify a mode of byte or __byte__ to indicate the mode correspond-
ing to a one-byte integer, word or __word__ for the mode of a one-word integer, and
pointer or __pointer__ for the mode used to represent pointers.
near
The near attribute tells the compiler that the variable is allocated in near data space
(the first 8 KB of data memory). Such variables can sometimes be accessed more
efficiently than variables not allocated (or not known to be allocated) in near data
space.
int num __attribute__ ((near));
noload
The noload attribute indicates that space should be allocated for the variable, but that
initial values should not be loaded. This attribute could be useful if an application is
designed to load a variable into memory at run time, such as from a serial EEPROM.
int table1[50] __attribute__ ((noload)) = { 0 };
page
The page attribute places variable definitions into a specific page of memory. The page
size depends on the type of memory selected by a space attribute. Objects residing in
RAM will be constrained to a 32K page while objects residing in Flash will be con-
strained to a 64K page (upper byte not included).
unsigned int var[10] __attribute__ ((space(auto_psv)));
The space(auto_psv) or space(psv) attribute will use a single memory page by
default.
__eds__ unsigned int var[10] __attribute__ ((eds, page));
When dealing with eds, please refer to Section 10.7 Extended Data Space Access
for more information.
packed
The packed attribute specifies that a structure member should have the smallest
possible alignment unless you specify a larger value with the aligned attribute.
Here is a structure in which the member x is packed, so that it immediately follows a,
with no padding for alignment:
struct foo
{
char a;
int x[2]
__attribute__ ((packed));
};
Note: The device architecture requires that words be aligned on even byte
boundaries, so care must be taken when using the packed attribute to
avoid run-time addressing errors.

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