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This compliant solution allows the structure to be treated as if it had declared the member {{data\[\]}} to be {{data\[array_size\]}} in a manner that conforms to the C99 standard.

However, some restrictions apply:

1. The incomplete array type must be the last element within the structure.
2. There cannot be an array of structures that contain flexible array members.
3. Structures that contain a flexible array member cannot be used as a member in the middle of another structure.
4. The sizeof operator cannot be applied to a flexible array.

Risk Assessment

Failing to use the correct syntax can result in undefined behavior, although the incorrect syntax will work on most implementations.

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