[clang] [analyzer] Make recognition of hardened __FOO_chk functions explicit (PR #86536)

[Balazs Benics via cfe-commits]

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@@ -124,34 +124,45 @@ class CStringChecker : public Checker< eval::Call,
                                      const CallEvent &)>;
 
   CallDescriptionMap<FnCheck> Callbacks = {
-      {{CDM::CLibrary, {"memcpy"}, 3},
+      {{CDM::CLibraryMaybeHardened, {"memcpy"}, 3},
        std::bind(&CStringChecker::evalMemcpy, _1, _2, _3, CK_Regular)},
-      {{CDM::CLibrary, {"wmemcpy"}, 3},
+      {{CDM::CLibraryMaybeHardened, {"wmemcpy"}, 3},
        std::bind(&CStringChecker::evalMemcpy, _1, _2, _3, CK_Wide)},
-      {{CDM::CLibrary, {"mempcpy"}, 3},
+      {{CDM::CLibraryMaybeHardened, {"mempcpy"}, 3},
        std::bind(&CStringChecker::evalMempcpy, _1, _2, _3, CK_Regular)},
-      {{CDM::Unspecified, {"wmempcpy"}, 3},
+      {{CDM::CLibraryMaybeHardened, {"wmempcpy"}, 3},
        std::bind(&CStringChecker::evalMempcpy, _1, _2, _3, CK_Wide)},
       {{CDM::CLibrary, {"memcmp"}, 3},
        std::bind(&CStringChecker::evalMemcmp, _1, _2, _3, CK_Regular)},
       {{CDM::CLibrary, {"wmemcmp"}, 3},
        std::bind(&CStringChecker::evalMemcmp, _1, _2, _3, CK_Wide)},
-      {{CDM::CLibrary, {"memmove"}, 3},
+      {{CDM::CLibraryMaybeHardened, {"memmove"}, 3},
        std::bind(&CStringChecker::evalMemmove, _1, _2, _3, CK_Regular)},
-      {{CDM::CLibrary, {"wmemmove"}, 3},
+      {{CDM::CLibraryMaybeHardened, {"wmemmove"}, 3},
        std::bind(&CStringChecker::evalMemmove, _1, _2, _3, CK_Wide)},
-      {{CDM::CLibrary, {"memset"}, 3}, &CStringChecker::evalMemset},
+      {{CDM::CLibraryMaybeHardened, {"memset"}, 3},
+       &CStringChecker::evalMemset},
       {{CDM::CLibrary, {"explicit_memset"}, 3}, &CStringChecker::evalMemset},
-      {{CDM::CLibrary, {"strcpy"}, 2}, &CStringChecker::evalStrcpy},
-      {{CDM::CLibrary, {"strncpy"}, 3}, &CStringChecker::evalStrncpy},
-      {{CDM::CLibrary, {"stpcpy"}, 2}, &CStringChecker::evalStpcpy},
-      {{CDM::CLibrary, {"strlcpy"}, 3}, &CStringChecker::evalStrlcpy},
-      {{CDM::CLibrary, {"strcat"}, 2}, &CStringChecker::evalStrcat},
-      {{CDM::CLibrary, {"strncat"}, 3}, &CStringChecker::evalStrncat},
-      {{CDM::CLibrary, {"strlcat"}, 3}, &CStringChecker::evalStrlcat},
-      {{CDM::CLibrary, {"strlen"}, 1}, &CStringChecker::evalstrLength},
+      /* FIXME: C23 introduces 'memset_explicit', maybe also model that */
----------------
steakhal wrote:

```suggestion
      // FIXME: C23 introduces 'memset_explicit', maybe also model that
```
I'd prefer single-line comments to be able comment out sections of this CDM when debugging.

https://github.com/llvm/llvm-project/pull/86536