[libcxx-commits] [PATCH] D148693: [libc++] Set correct size at the end of growing std::string

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This revision adds setting a correct size at the end of `__grow_by`.
Without it, the function may not keep strings invariants.

Size may be incorrect after growing a string from short (SSO) to long, as place where size is kept could be changed.

This causes problems in D132769 <https://reviews.llvm.org/D132769> and originally was addressed there.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D148693

Files:
  libcxx/include/string


Index: libcxx/include/string
===================================================================
--- libcxx/include/string
+++ libcxx/include/string
@@ -2286,6 +2286,7 @@
         __alloc_traits::deallocate(__alloc(), __old_p, __old_cap + 1);
     __set_long_pointer(__p);
     __set_long_cap(__allocation.count);
+    __set_long_size(__old_sz);
 }
 
 // assign


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