C++: Fix a crazy FP in cpp/leap-year/unsafe-array-for-days-of-the-year

cpp/ql/src/Likely Bugs/Leap Year/UnsafeArrayForDaysOfYear.ql

@@ -26,6 +26,7 @@ where
   or
   exists(Variable var |
     var = element and
+    not var.isCompilerGenerated() and
     var.getType() instanceof LeapYearUnsafeDaysOfTheYearArrayType and
     allocType = "an array allocation"
   )

cpp/ql/src/change-notes/2026-08-28-leap-year-unsafe-array-fp.md

@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* The `cpp/leap-year/unsafe-array-for-days-of-the-year` query ("Unsafe array for days of the year") no longer reports an alert on the `__PRETTY_FUNCTION__` variable (and related variables) when the enclosing function has a signature that is exactly 364 characters.

cpp/ql/test/query-tests/Likely Bugs/Leap Year/UnsafeArrayForDaysOfYear/test.cpp

@@ -68,3 +68,12 @@ void VectorOfDays_FalsePositive(int dayOfYear, int x)
 
 	items[dayOfYear - 1] = x;
 }
+
+void f_______________________________________________________this_name_must_be_exactly_357_chars__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________() {
+  // Using this magic compiler variable results in a `const char` array being
+  // initialized with the function signature. Including `void`, a space, and
+  // `()`, the signature adds up to exactly 364 characters in this case.
+  // The initializer for `__PRETTY_FUNCTION__` thus initializes an array of
+  // length 365 (because the null-terminator adds another character).
+  auto x = __PRETTY_FUNCTION__; // clean
+}