[PATCH] D144429: [clang-tidy] Add bugprone-chained-comparison check

[Piotr Zegar via Phabricator via cfe-commits]

PiotrZSL added a comment.

Ping


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[PATCH] D144429: [clang-tidy] Add bugprone-chained-comparison check

[Piotr Zegar via Phabricator via cfe-commits]

PiotrZSL updated this revision to Diff 551758.
PiotrZSL added a comment.

Rebase + Ping


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
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Files:
  clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
  clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.cpp
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.h
  clang-tools-extra/docs/ReleaseNotes.rst
  clang-tools-extra/docs/clang-tidy/checks/bugprone/chained-comparison.rst
  clang-tools-extra/docs/clang-tidy/checks/list.rst
  clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp

Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
===
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
@@ -0,0 +1,91 @@
+// RUN: %check_clang_tidy -std=c++98-or-later %s bugprone-chained-comparison %t
+
+void badly_chained_1(int x, int y, int z)
+{
+bool result = x < y < z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_2(int x, int y, int z)
+{
+bool result = x <= y <= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a <= b <= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_3(int x, int y, int z)
+{
+bool result = x > y > z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a > b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_4(int x, int y, int z)
+{
+bool result = x >= y >= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a >= b >= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_5(int x, int y, int z)
+{
+bool result = x == y != z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b != c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_6(bool x, bool y, bool z)
+{
+bool result = x != y == z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a != b == c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_multiple(bool a, bool b, bool c, bool d, bool e, bool f, bool g, bool h)
+{
+bool result = a == b == c == d == e == f == g == h;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_limit(bool v[29])
+{
+// CHECK-MESSAGES: :[[@LINE+1]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h == i == j == k == l == m == n == o == p == q == r == s == t == u == v == w == x == y == z ...' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+bool result = v[0] == v[1] == v[2] == v[3] == v[4] == v[5] == v[6] == v[7] ==
+  v[8] == v[9] == v[10] == v[11] == v[12] == v[13] == v[14] ==
+  v[15] == v[16] == v[17] == v[18] == v[19] == v[20] == v[21] ==
+  v[22] == v[23] == v[24] == v[25] == v[26] == v[27] == v[28];
+
+}
+
+void badly_chained_parens2(int x, int y, int z, int t, int a, int b)
+{
+bool result = (x < y) < (z && t) > (a == b);
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_inner(int x, int y, int z, int t, int u)
+{
+bool result = x && y < z < t && u;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:24: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void properly_chained_1(int x, int y, int z)
+{
+bool 

[PATCH] D144429: [clang-tidy] Add bugprone-chained-comparison check

[Piotr Zegar via Phabricator via cfe-commits]

PiotrZSL added a comment.

Ping


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[PATCH] D144429: [clang-tidy] Add bugprone-chained-comparison check

[Piotr Zegar via Phabricator via cfe-commits]

PiotrZSL added a comment.

Ping


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[PATCH] D144429: [clang-tidy] Add bugprone-chained-comparison check

[Piotr Zegar via Phabricator via cfe-commits]

PiotrZSL updated this revision to Diff 518342.
PiotrZSL added a comment.

Ping, Rebase


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D144429/new/

https://reviews.llvm.org/D144429

Files:
  clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
  clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.cpp
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.h
  clang-tools-extra/docs/ReleaseNotes.rst
  clang-tools-extra/docs/clang-tidy/checks/bugprone/chained-comparison.rst
  clang-tools-extra/docs/clang-tidy/checks/list.rst
  clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp

Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
===
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
@@ -0,0 +1,91 @@
+// RUN: %check_clang_tidy -std=c++98-or-later %s bugprone-chained-comparison %t
+
+void badly_chained_1(int x, int y, int z)
+{
+bool result = x < y < z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_2(int x, int y, int z)
+{
+bool result = x <= y <= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a <= b <= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_3(int x, int y, int z)
+{
+bool result = x > y > z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a > b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_4(int x, int y, int z)
+{
+bool result = x >= y >= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a >= b >= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_5(int x, int y, int z)
+{
+bool result = x == y != z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b != c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_6(bool x, bool y, bool z)
+{
+bool result = x != y == z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a != b == c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_multiple(bool a, bool b, bool c, bool d, bool e, bool f, bool g, bool h)
+{
+bool result = a == b == c == d == e == f == g == h;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_limit(bool v[29])
+{
+// CHECK-MESSAGES: :[[@LINE+1]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h == i == j == k == l == m == n == o == p == q == r == s == t == u == v == w == x == y == z ...' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+bool result = v[0] == v[1] == v[2] == v[3] == v[4] == v[5] == v[6] == v[7] ==
+  v[8] == v[9] == v[10] == v[11] == v[12] == v[13] == v[14] ==
+  v[15] == v[16] == v[17] == v[18] == v[19] == v[20] == v[21] ==
+  v[22] == v[23] == v[24] == v[25] == v[26] == v[27] == v[28];
+
+}
+
+void badly_chained_parens2(int x, int y, int z, int t, int a, int b)
+{
+bool result = (x < y) < (z && t) > (a == b);
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_inner(int x, int y, int z, int t, int u)
+{
+bool result = x && y < z < t && u;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:24: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void properly_chained_1(int x, int y, int z)
+{
+bool 

[PATCH] D144429: [clang-tidy] Add bugprone-chained-comparison check

[Piotr Zegar via Phabricator via cfe-commits]

PiotrZSL updated this revision to Diff 503362.
PiotrZSL added a comment.

Rebase due to broken baseline


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D144429/new/

https://reviews.llvm.org/D144429

Files:
  clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
  clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.cpp
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.h
  clang-tools-extra/docs/ReleaseNotes.rst
  clang-tools-extra/docs/clang-tidy/checks/bugprone/chained-comparison.rst
  clang-tools-extra/docs/clang-tidy/checks/list.rst
  clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp

Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
===
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
@@ -0,0 +1,91 @@
+// RUN: %check_clang_tidy -std=c++98-or-later %s bugprone-chained-comparison %t
+
+void badly_chained_1(int x, int y, int z)
+{
+bool result = x < y < z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_2(int x, int y, int z)
+{
+bool result = x <= y <= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a <= b <= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_3(int x, int y, int z)
+{
+bool result = x > y > z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a > b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_4(int x, int y, int z)
+{
+bool result = x >= y >= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a >= b >= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_5(int x, int y, int z)
+{
+bool result = x == y != z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b != c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_6(bool x, bool y, bool z)
+{
+bool result = x != y == z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a != b == c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_multiple(bool a, bool b, bool c, bool d, bool e, bool f, bool g, bool h)
+{
+bool result = a == b == c == d == e == f == g == h;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_limit(bool v[29])
+{
+// CHECK-MESSAGES: :[[@LINE+1]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h == i == j == k == l == m == n == o == p == q == r == s == t == u == v == w == x == y == z ...' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+bool result = v[0] == v[1] == v[2] == v[3] == v[4] == v[5] == v[6] == v[7] ==
+  v[8] == v[9] == v[10] == v[11] == v[12] == v[13] == v[14] ==
+  v[15] == v[16] == v[17] == v[18] == v[19] == v[20] == v[21] ==
+  v[22] == v[23] == v[24] == v[25] == v[26] == v[27] == v[28];
+
+}
+
+void badly_chained_parens2(int x, int y, int z, int t, int a, int b)
+{
+bool result = (x < y) < (z && t) > (a == b);
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_inner(int x, int y, int z, int t, int u)
+{
+bool result = x && y < z < t && u;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:24: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void properly_chained_1(int x, int y, int 

[PATCH] D144429: [clang-tidy] Add bugprone-chained-comparison check

[Piotr Zegar via Phabricator via cfe-commits]

PiotrZSL updated this revision to Diff 503312.
PiotrZSL added a comment.

Ping, Rebase


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D144429/new/

https://reviews.llvm.org/D144429

Files:
  clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
  clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.cpp
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.h
  clang-tools-extra/docs/ReleaseNotes.rst
  clang-tools-extra/docs/clang-tidy/checks/bugprone/chained-comparison.rst
  clang-tools-extra/docs/clang-tidy/checks/list.rst
  clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp

Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
===
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
@@ -0,0 +1,91 @@
+// RUN: %check_clang_tidy -std=c++98-or-later %s bugprone-chained-comparison %t
+
+void badly_chained_1(int x, int y, int z)
+{
+bool result = x < y < z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_2(int x, int y, int z)
+{
+bool result = x <= y <= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a <= b <= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_3(int x, int y, int z)
+{
+bool result = x > y > z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a > b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_4(int x, int y, int z)
+{
+bool result = x >= y >= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a >= b >= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_5(int x, int y, int z)
+{
+bool result = x == y != z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b != c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_6(bool x, bool y, bool z)
+{
+bool result = x != y == z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a != b == c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_multiple(bool a, bool b, bool c, bool d, bool e, bool f, bool g, bool h)
+{
+bool result = a == b == c == d == e == f == g == h;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_limit(bool v[29])
+{
+// CHECK-MESSAGES: :[[@LINE+1]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h == i == j == k == l == m == n == o == p == q == r == s == t == u == v == w == x == y == z ...' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+bool result = v[0] == v[1] == v[2] == v[3] == v[4] == v[5] == v[6] == v[7] ==
+  v[8] == v[9] == v[10] == v[11] == v[12] == v[13] == v[14] ==
+  v[15] == v[16] == v[17] == v[18] == v[19] == v[20] == v[21] ==
+  v[22] == v[23] == v[24] == v[25] == v[26] == v[27] == v[28];
+
+}
+
+void badly_chained_parens2(int x, int y, int z, int t, int a, int b)
+{
+bool result = (x < y) < (z && t) > (a == b);
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_inner(int x, int y, int z, int t, int u)
+{
+bool result = x && y < z < t && u;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:24: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void properly_chained_1(int x, int y, int z)
+{
+bool 

[PATCH] D144429: [clang-tidy] Add bugprone-chained-comparison check

[Piotr Zegar via Phabricator via cfe-commits]

PiotrZSL created this revision.
Herald added subscribers: carlosgalvezp, xazax.hun.
Herald added a reviewer: njames93.
Herald added a project: All.
PiotrZSL added a comment.
PiotrZSL published this revision for review.
Herald added a project: clang-tools-extra.
Herald added a subscriber: cfe-commits.

Note that looks like there is currently in implementation new warning 
-Wcomparison-op-parentheses under D142800 , 
that warning currently handle only chained comparison by using BinaryOperator, 
not by using CXXOperatorCallExpr.
Scope of "-Wcomparison-op-parentheses" and whatever that warning will be 
delivered in LLVM 17 will determinate future of this check.
This check is feature-complete.


Check that flags chained comparison expressions,
such as a < b < c or a == b == c, which may have
unintended behavior due to implicit operator
associativity.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D144429

Files:
  clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
  clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.cpp
  clang-tools-extra/clang-tidy/bugprone/ChainedComparisonCheck.h
  clang-tools-extra/docs/ReleaseNotes.rst
  clang-tools-extra/docs/clang-tidy/checks/bugprone/chained-comparison.rst
  clang-tools-extra/docs/clang-tidy/checks/list.rst
  clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp

Index: clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
===
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone/chained-comparison.cpp
@@ -0,0 +1,91 @@
+// RUN: %check_clang_tidy -std=c++98-or-later %s bugprone-chained-comparison %t
+
+void badly_chained_1(int x, int y, int z)
+{
+bool result = x < y < z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a < b < c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_2(int x, int y, int z)
+{
+bool result = x <= y <= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a <= b <= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_3(int x, int y, int z)
+{
+bool result = x > y > z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a > b > c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_4(int x, int y, int z)
+{
+bool result = x >= y >= z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a >= b >= c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_5(int x, int y, int z)
+{
+bool result = x == y != z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b != c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_6(bool x, bool y, bool z)
+{
+bool result = x != y == z;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a != b == c' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_multiple(bool a, bool b, bool c, bool d, bool e, bool f, bool g, bool h)
+{
+bool result = a == b == c == d == e == f == g == h;
+}
+// CHECK-MESSAGES: :[[@LINE-2]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+
+void badly_chained_limit(bool v[29])
+{
+// CHECK-MESSAGES: :[[@LINE+1]]:19: warning: chained comparison 'a == b == c == d == e == f == g == h == i == j == k == l == m == n == o == p == q == r == s == t == u == v == w == x == y == z ...' may generate unintended results, use parentheses to specify order of evaluation or a logical operator to separate comparison expressions [bugprone-chained-comparison]
+bool result = v[0] == v[1] == v[2] == v[3] == v[4] == v[5] == v[6] == v[7] ==
+  v[8] == v[9] == v[10] == v[11] == v[12] == v[13] == v[14] ==
+  v[15] == v[16] == v[17] == v[18] == v[19] == v[20] == v[21] ==
+  v[22] == v[23] == v[24] == v[25] == v[26] == v[27] == v[28];
+
+}
+
+void badly_chained_parens2(int x, int y, int