__attribute__ is a GNU extension that allows to decorate functions, parameters, variables… with some attributes. It may help for
compiler optimizations or for the writer of some code to better state his intent (and have the compiler check it).
If this extension is used incorrectly, it will usually not break the build, but it still means that the code may not behave as the developer
expects. This rule reports such occurrences of bad use of __attribute__.
Noncompliant code example
int f1() __attribute__((returns_nonnull)); // Noncompliant; "returns_nonnull" only applies to return values which are pointers
void g(int *a) __attribute__((nonnull(1))){} // Noncompliant; "nonnull" position in the function definition is not allowed
void h() __attribute__((warn_unused_result)); // Noncompliant; "warn_unused_result" does not work with function without return value
void test() {
int __declspec(empty_bases)i; // Noncompliant; "empty_bases" only applies to classes
char c = (char __attribute__((aligned(8)))) i; // Noncompliant, attribute is ignored
}}
