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Padding is also referred to as " struct member alignment. " Many compilers provide a flag that controls how the members of a structure are packed into memory. Modifying this flag may cause the size of the structures to vary. Most compilers also include a keyword that removes all padding; the resulting structures are referred to as packed structures. Overriding the default behavior is often unwise because it leads to interface compatibility problems (the nominally same struct has its layout interpreted differently in different modules).
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