[clang] [clang] Fix sorting header paths (PR #73323)

[Tulio Magno Quites Machado Filho via cfe-commits]

https://github.com/tuliom created https://github.com/llvm/llvm-project/pull/73323

This code was initially written in commit
7ff29148ac7883881e62dc9e1714057c68ad4436 with the intention of sorting headers according to their path. At the time, the path was saved in field NameAsWritten of Module::Header.

Later, commit e6830b6028ec5434ccf8dbebdd992918f67b1751 added field PathRelativeToRootModuleDirectory to Module::Header and modified ModuleMapParser::parseUmbrellaDirDecl() so that it started to save the header path in the new field and started setting NameAsWritten = "". It didn't modify compareModuleHeaders() in order to adapt it to the new field.

After this commit, the sorting stopped working because it continued comparing only NameAsWritten.

This commit fixes it by treating NameAsWritten and PathRelativeToRootModuleDirectory as a tuple when comparing Module::Header.

>From 772d51724dda39baa7347f2c33af5c65786964a2 Mon Sep 17 00:00:00 2001
From: Tulio Magno Quites Machado Filho <tuliom at redhat.com>
Date: Fri, 24 Nov 2023 09:26:12 -0300
Subject: [PATCH] [clang] Fix sorting header paths

This code was initially written in commit
7ff29148ac7883881e62dc9e1714057c68ad4436 with the intention of sorting
headers according to their path. At the time, the path was saved in
field NameAsWritten of Module::Header.

Later, commit e6830b6028ec5434ccf8dbebdd992918f67b1751 added field
PathRelativeToRootModuleDirectory to Module::Header and modified
ModuleMapParser::parseUmbrellaDirDecl() so that it started to save the
header path in the new field and started setting NameAsWritten = "".
It didn't modify compareModuleHeaders() in order to adapt it to the new
field.

After this commit, the sorting stopped working because it continued
comparing only NameAsWritten.

This commit fixes it by treating NameAsWritten and
PathRelativeToRootModuleDirectory as a tuple when comparing Module::Header.
---
 clang/lib/Lex/ModuleMap.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Lex/ModuleMap.cpp b/clang/lib/Lex/ModuleMap.cpp
index 1d67e275cb4775a..7bc89b2fed36bf2 100644
--- a/clang/lib/Lex/ModuleMap.cpp
+++ b/clang/lib/Lex/ModuleMap.cpp
@@ -49,6 +49,7 @@
 #include <optional>
 #include <string>
 #include <system_error>
+#include <tuple>
 #include <utility>
 
 using namespace clang;
@@ -2511,7 +2512,8 @@ void ModuleMapParser::parseHeaderDecl(MMToken::TokenKind LeadingToken,
 
 static bool compareModuleHeaders(const Module::Header &A,
                                  const Module::Header &B) {
-  return A.NameAsWritten < B.NameAsWritten;
+  return std::tie(A.NameAsWritten, A.PathRelativeToRootModuleDirectory) <
+         std::tie(B.NameAsWritten, B.PathRelativeToRootModuleDirectory);
 }
 
 /// Parse an umbrella directory declaration.