[libcxx-commits] [PATCH] D123058: [libc++] Remove the usage of __init in operator+

[Louis Dionne via Phabricator via libcxx-commits]

ldionne requested changes to this revision.
ldionne added inline comments.
This revision now requires changes to proceed.


================
Comment at: libcxx/include/string:767
 
+    _LIBCPP_HIDE_FROM_ABI basic_string(__uninitialized_size_tag, size_type __size, const allocator_type& __a)
+            : __r_(__default_init_tag(), __a) {
----------------
Let's make it `explicit`.

Can you also add a comment documenting what this constructor does? Something like:

```
// Construct a string with the given allocator and enough storage to hold `__size` characters, but
// don't initialize the characters. The contents of the string, including the null terminator, must be
// initialized separately.
```


================
Comment at: libcxx/include/string:769
+            : __r_(__default_init_tag(), __a) {
+        if (__fits_in_sso(__size)) {
+            __zero();
----------------
We need to handle the case where `__size > max_size()` like we used to in `__init`.


================
Comment at: libcxx/include/string:4207
+    _Traits::copy(__r.data() + __lhs_sz, __rhs.data(), __rhs_sz);
+    _Traits::assign(__r.data() + __lhs_sz + __rhs_sz, 1, '\0');
     return __r;
----------------
This would need to be `value_type()` instead of `'\0'`. We support non-`char` character types as well.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D123058/new/

https://reviews.llvm.org/D123058