[clang] [clang-format] Fix crashes in AlignArrayOfStructures (PR #72520)

[Owen Pan via cfe-commits]

https://github.com/owenca created https://github.com/llvm/llvm-project/pull/72520

Fixed #55493.
Fixed #68431.

>From efdf321e9447e8b3f1c27ccdf6da842107deb6dd Mon Sep 17 00:00:00 2001
From: Owen Pan <owenpiano at gmail.com>
Date: Thu, 16 Nov 2023 06:36:41 -0800
Subject: [PATCH] [clang-format] Fix crashes in AlignArrayOfStructures

Fixed #55493.
Fixed #68431.
---
 clang/lib/Format/WhitespaceManager.cpp |  4 +++-
 clang/lib/Format/WhitespaceManager.h   |  2 +-
 clang/unittests/Format/FormatTest.cpp  | 18 ++++++++++++++++++
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Format/WhitespaceManager.cpp b/clang/lib/Format/WhitespaceManager.cpp
index 32d8b97cc8dadb1..3bc6915b8df0a70 100644
--- a/clang/lib/Format/WhitespaceManager.cpp
+++ b/clang/lib/Format/WhitespaceManager.cpp
@@ -1316,6 +1316,8 @@ void WhitespaceManager::alignArrayInitializersRightJustified(
         auto Offset = std::distance(Cells.begin(), CellIter);
         for (const auto *Next = CellIter->NextColumnElement; Next;
              Next = Next->NextColumnElement) {
+          if (RowCount >= CellDescs.CellCounts.size())
+            break;
           auto *Start = (Cells.begin() + RowCount * CellDescs.CellCounts[0]);
           auto *End = Start + Offset;
           ThisNetWidth = getNetWidth(Start, End, CellDescs.InitialSpaces);
@@ -1379,7 +1381,7 @@ void WhitespaceManager::alignArrayInitializersLeftJustified(
     auto Offset = std::distance(Cells.begin(), CellIter);
     for (const auto *Next = CellIter->NextColumnElement; Next;
          Next = Next->NextColumnElement) {
-      if (RowCount > CellDescs.CellCounts.size())
+      if (RowCount >= CellDescs.CellCounts.size())
         break;
       auto *Start = (Cells.begin() + RowCount * CellDescs.CellCounts[0]);
       auto *End = Start + Offset;
diff --git a/clang/lib/Format/WhitespaceManager.h b/clang/lib/Format/WhitespaceManager.h
index df7e9add1cd446f..69398fe411502f1 100644
--- a/clang/lib/Format/WhitespaceManager.h
+++ b/clang/lib/Format/WhitespaceManager.h
@@ -317,7 +317,7 @@ class WhitespaceManager {
     auto Offset = std::distance(CellStart, CellStop);
     for (const auto *Next = CellStop->NextColumnElement; Next;
          Next = Next->NextColumnElement) {
-      if (RowCount > MaxRowCount)
+      if (RowCount >= MaxRowCount)
         break;
       auto Start = (CellStart + RowCount * CellCount);
       auto End = Start + Offset;
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index a12a20359c2fad2..cd4c93e8427723f 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -21140,6 +21140,24 @@ TEST_F(FormatTest, CatchAlignArrayOfStructuresLeftAlignment) {
       "that really, in any just world, ought to be split over multiple "
       "lines\"},{-1, 93463, \"world\"},{7, 5, \"!!\"},};",
       Style);
+
+  Style.ColumnLimit = 25;
+  verifyNoCrash("Type object[X][Y] = {\n"
+                "    {{val}, {val}, {val}},\n"
+                "    {{val}, {val}, // some comment\n"
+                "                   {val}}\n"
+                "};",
+                Style);
+
+  Style.ColumnLimit = 120;
+  verifyNoCrash(
+      "T v[] {\n"
+      "    { AAAAAAAAAAAAAAAAAAAAAAAAA::aaaaaaaaaaaaaaaaaaa, "
+      "AAAAAAAAAAAAAAAAAAAAAAAAA::aaaaaaaaaaaaaaaaaaaaaaaa, 1, 0.000000000f, "
+      "\"00000000000000000000000000000000000000000000000000000000"
+      "00000000000000000000000000000000000000000000000000000000\" },\n"
+      "};",
+      Style);
 }
 
 TEST_F(FormatTest, UnderstandsPragmas) {