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userland/cpp/constexpr_func_infinite_loop.cpp

@@ -0,0 +1,22 @@
+// https://cirosantilli.com/linux-kernel-module-cheat#cpp
+
+constexpr int f() {
+    int i = 0;
+    while (1)
+        i += 1;
+    return i;
+}
+
+constexpr int g() {
+    return g();
+}
+
+
+int main() {
+#if 0
+    // GCC 9.2.1. error: ‘constexpr’ loop iteration count exceeds limit of 262144 (use ‘-fconstexpr-loop-limit=’ to increase the limit)
+    static_assert(f() == 0);
+    // GCC 9.2.1. error: ‘constexpr’ evaluation depth exceeds maximum of 512 (use ‘-fconstexpr-depth=’ to increase the maximum)
+    static_assert(g() == 0);
+#endif
+}