[clang] 302cb3b - [Syntax] Add a comment explaining the pointer keys in std::map<Token*, ...>. NFC

[Ilya Biryukov via cfe-commits]

Author: Ilya Biryukov
Date: 2019-11-29T09:49:24+01:00
New Revision: 302cb3bc3d7220e09f5dced64ddfdda33b9c49f9

URL: https://github.com/llvm/llvm-project/commit/302cb3bc3d7220e09f5dced64ddfdda33b9c49f9
DIFF: https://github.com/llvm/llvm-project/commit/302cb3bc3d7220e09f5dced64ddfdda33b9c49f9.diff

LOG: [Syntax] Add a comment explaining the pointer keys in std::map<Token*, ...>. NFC

Added: 
    

Modified: 
    clang/lib/Tooling/Syntax/BuildTree.cpp

Removed: 
    


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diff  --git a/clang/lib/Tooling/Syntax/BuildTree.cpp b/clang/lib/Tooling/Syntax/BuildTree.cpp
index b36b8e00f7c1..22cdb89b7bfb 100644
--- a/clang/lib/Tooling/Syntax/BuildTree.cpp
+++ b/clang/lib/Tooling/Syntax/BuildTree.cpp
@@ -209,6 +209,8 @@ class syntax::TreeBuilder {
     };
 
     /// Maps from the start token to a subtree starting at that token.
+    /// Keys in the map are pointers into the array of expanded tokens, so
+    /// pointer order corresponds to the order of preprocessor tokens.
     /// FIXME: storing the end tokens is redundant.
     /// FIXME: the key of a map is redundant, it is also stored in NodeForRange.
     std::map<const syntax::Token *, NodeAndRole> Trees;