[PATCH] D26332: Add a user-defined literal for StringRef

[Malcolm Parsons via llvm-commits]

malcolm.parsons added inline comments.


================
Comment at: include/llvm/ADT/StringRef.h:74
     /// Construct an empty string ref.
-    /*implicit*/ StringRef() : Data(nullptr), Length(0) {}
+    /*implicit*/ constexpr StringRef() : Data(nullptr), Length(0) {}
 
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mehdi_amini wrote:
> Is this related to this patch?
No.


================
Comment at: include/llvm/ADT/StringRef.h:88
     /*implicit*/ StringRef(const char *data, size_t length)
-      : Data(data), Length(length) {
-        assert((data || length == 0) &&
-        "StringRef cannot be built from a NULL argument with non-null length");
-      }
+        : Data(data), Length(data ? length : 0) {}
 
----------------
mehdi_amini wrote:
> same.
Yes. This constructor needs to be constexpr, so that the constexpr UDL can call it. It can't use assert in C++11.


================
Comment at: lib/CodeGen/AsmPrinter/DIEHash.cpp:41
 
-  return StringRef("");
+  return ""_sr;
 }
----------------
mehdi_amini wrote:
> Why not just `return "";`?
I wonder this about the original.
These transformations were made with sed.


https://reviews.llvm.org/D26332