From b73aeeda0e16268e9d65f51b5db429a4da50ff85 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Wed, 6 Apr 2022 16:58:17 +0200
Subject: [PATCH] Fix FP constStatement with comma operator (#3978)

* Fix FP constStatement with comma operator

* Format
---
 lib/checkother.cpp               |  4 ++--
 test/testincompletestatement.cpp | 10 ++++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/lib/checkother.cpp b/lib/checkother.cpp
index 1e0303b9a..a94ea363f 100644
--- a/lib/checkother.cpp
+++ b/lib/checkother.cpp
@@ -1792,11 +1792,11 @@ static bool isConstStatement(const Token *tok, bool cpp)
         if (tok->astParent()) // warn about const statement on rhs at the top level
             return isConstStatement(tok->astOperand1(), cpp) && isConstStatement(tok->astOperand2(), cpp);
         else {
-            const Token* lml = previousBeforeAstLeftmostLeaf(tok);
+            const Token* lml = previousBeforeAstLeftmostLeaf(tok); // don't warn about matrix/vector assignment (e.g. Eigen)
             if (lml)
                 lml = lml->next();
             const Token* stream = lml;
-            while (stream && Token::Match(stream->astParent(), ".|[|("))
+            while (stream && Token::Match(stream->astParent(), ".|[|(|*"))
                 stream = stream->astParent();
             return (!stream || !isLikelyStream(cpp, stream)) && isConstStatement(tok->astOperand2(), cpp);
         }
diff --git a/test/testincompletestatement.cpp b/test/testincompletestatement.cpp
index e3b97c996..8f6bc0e0c 100644
--- a/test/testincompletestatement.cpp
+++ b/test/testincompletestatement.cpp
@@ -396,6 +396,16 @@ private:
               "    a.b[4][3].c()->d << x , y, z;\n"
               "}\n");
         ASSERT_EQUALS("", errout.str());
+
+        check("struct V {\n"
+              "    Eigen::Vector3d& operator[](int i) { return v[i]; }\n"
+              "    void f(int a, int b, int c);\n"
+              "    Eigen::Vector3d v[1];\n"
+              "};\n"
+              "void V::f(int a, int b, int c) {\n"
+              "    (*this)[0] << a, b, c;\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     // #8451