/*
* Note: do not use this directly. Instead, use __alloc_size() since it is conditionally
- * available and includes other attributes.
+ * available and includes other attributes. For GCC < 9.1, __alloc_size__ gets undefined
+ * in compiler-gcc.h, due to misbehaviors.
*
* gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-alloc_005fsize-function-attribute
* clang: https://clang.llvm.org/docs/AttributeReference.html#alloc-size