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#include <string.h> #include <stddef.h> #include <limits.h> inth> #include <stddef.h> #include <limits.h> int *init_memory(int *array, size_t n) { return memset(array, 4096, n); } |
Compliant Solution (memset())
In general, the memset()
function should not be used to initialize an integer array unless it is to set or clear all the bits.
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#include <string.h> #include <stddef.h> #include <limits.h> inth> #include <stddef.h> #include <limits.h> int *init_memory(int *array, size_t n) { return memset(array, 0, n); } |
Exceptions
INT31-EX1: The C Standard defines minimum ranges for standard integer types. For example, the minimum range for an object of type unsigned short int
is 0 to 65,535, whereas the minimum range for int
is −32,767 to +32,767. Consequently, it is not always possible to represent all possible values of an unsigned short int
as an int
. However, on the IA-32 architecture, for example, the actual integer range is from −2,147,483,648 to +2,147,483,647, meaning that it is quite possible to represent all the values of an unsigned short int
as an int
for this architecture. As a result, it is not necessary to provide a test for this conversion on IA-32. It is not possible to make assumptions about conversions without knowing the precision of the underlying types. If these tests are not provided, assumptions concerning precision must be clearly documented, as the resulting code cannot be safely ported to a system where these assumptions are invalid. A good way to document these assumptions is to use static assertions (see DCL03-C. Use a static assertion to test the value of a constant expression).
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