https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112795
Bug ID: 112795
Summary: [C++>=14] ICE pragma GCC unroll (n)
cxx_eval_constant_expression
Product: gcc
Version: 8.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: magnus.hegdahl at gmail dot com
Target Milestone: ---
Compiling the following code with GCC >= 8.1 (when #pragma GCC unroll was
added), and -std=c++14 or higher results in an internal compiler error:
```
constexpr int n = 1;
template <class = void>
void f() {
#pragma GCC unroll(n)
for (int i = 0; i != n; ++i) {
}
}
```
It does not fail if f is not a template, if n is not parenthesized, or if using
-std=c++11.
