[clang] [NFC][analyzer] Remove non-const CheckerContext::isDifferent (PR #218937)

[Donát Nagy via cfe-commits]

https://github.com/NagyDonat updated https://github.com/llvm/llvm-project/pull/218937

>From 7152d4b8458978690af577ffa258d32015caf807 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Don=C3=A1t=20Nagy?= <donat.nagy at ericsson.com>
Date: Wed, 26 Aug 2026 15:49:45 +0200
Subject: [PATCH 1/2] [NFC][analyzer] Remove non-const
 CheckerContext::isDifferent

The method `CheckerContext::isDifferent` should be a `const` method (it
does not modify `*this`), but it was originally declared as non-`const`
and later commit f93f6e5259e32a00921c66561f3117356a779a01 introduced the
`const` variant as an overload along the non-`const` original variant.

As the non-`const` overload is does not have any advantage, this commit
removes it. (In many other cases a separate non-`const` overload is
needed because the `const` overload has `const` in its return type, but
here both overloads return the same `bool`.)
---
 .../clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h     | 1 -
 1 file changed, 1 deletion(-)

diff --git a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
index 38bcd55354a63..1262dbea88715 100644
--- a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
+++ b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
@@ -83,7 +83,6 @@ class CheckerContext {
 
   /// Check if the checker changed the state of the execution; ex: added
   /// a new transition or a bug report.
-  bool isDifferent() { return Changed; }
   bool isDifferent() const { return Changed; }
 
   /// Returns the number of times the current block has been visited

>From dc2e813f20e1134cb4c84e82e0cae7b5edf84204 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Don=C3=A1t=20Nagy?= <donat.nagy at ericsson.com>
Date: Wed, 26 Aug 2026 16:47:25 +0200
Subject: [PATCH 2/2] Unify overloads of CheckerContext::getPredecessor()

We can return a pointer to a non-const `ExplodedNode` even if `*this` is
const. (Note that `ExplodedNode`s are almost always non-const because
`addPredecessor()` is a non-`const` method).
---
 .../clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h   | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
index 1262dbea88715..6463bad3de6ab 100644
--- a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
+++ b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
@@ -76,8 +76,7 @@ class CheckerContext {
   /// Returns the previous node in the exploded graph, which includes
   /// the state of the program before the checker ran. Note, checkers should
   /// not retain the node in their state since the nodes might get invalidated.
-  ExplodedNode *getPredecessor() { return Pred; }
-  const ExplodedNode *getPredecessor() const { return Pred; }
+  ExplodedNode *getPredecessor() const { return Pred; }
   const ProgramPoint getLocation() const { return Location; }
   const ProgramStateRef &getState() const { return Pred->getState(); }