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The following noncompliant code example declares matrix to consist of 7 rows and 5 columns in row-major order. The function init_matrix then iterates over all 35 elements in an attempt to initialize each to the value given by the function argument x. However, since because multidimensional arrays are declared in C in row-major order, and the function iterates over the elements in column-major order, and when the value of j reaches the value COLS during the first iteration of the outer loop, the function attempts to access element matrix[0][5]. Because the type of matrix is int[7][5], the j subscript is out of range, and the access has undefined behavior 49.
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In the following noncompliant code example the function find() attempts to iterate over the elements of the flexible array member buf, starting with the second element. However, since because function g() does not allocate any storage for the member, the expression first++ in find() attempts to form a pointer just past the end of buf when there are no elements. This attempt results in undefined behavior 62 .
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