https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121666
Bug ID: 121666
Summary: __builtin_expect_with_probability accepts non constant
expression
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: vincent at vvhe dot ca
Target Milestone: ---
In the documentation, it says that the probability must be a constant floating
point expression, so why does gcc accept the following code? It this a bug or a
feature that is not documented?
double rand_impl();
void foo (int i){
__builtin_expect_with_probability (i, 0, rand_impl());
}
Also, clang rejects the code from above for not being a constant expression:
https://godbolt.org/z/Eh7x4q3xr.
