[clang] c8010da - [analyzer][docs] Add basic description of checker 'core.CallAndMessage' (#177179)

[via cfe-commits]

Author: Balázs Kéri
Date: 2026-01-27T09:58:20+01:00
New Revision: c8010da017bb82066e36c5f8d12877cbc8ab2bbd

URL: https://github.com/llvm/llvm-project/commit/c8010da017bb82066e36c5f8d12877cbc8ab2bbd
DIFF: https://github.com/llvm/llvm-project/commit/c8010da017bb82066e36c5f8d12877cbc8ab2bbd.diff

LOG: [analyzer][docs] Add basic description of checker 'core.CallAndMessage' (#177179)

The checker had very little documentation. Now a more detailed (but
still not much) description of the features and options is added.

Added: 
    

Modified: 
    clang/docs/analyzer/checkers.rst

Removed: 
    


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diff  --git a/clang/docs/analyzer/checkers.rst b/clang/docs/analyzer/checkers.rst
index e449593e95d21..ecddda1f0737f 100644
--- a/clang/docs/analyzer/checkers.rst
+++ b/clang/docs/analyzer/checkers.rst
@@ -83,7 +83,49 @@ Ensure the shift operands are in proper range before shifting.
 
 core.CallAndMessage (C, C++, ObjC)
 """"""""""""""""""""""""""""""""""
- Check for logical errors for function calls and Objective-C message expressions (e.g., uninitialized arguments, null function pointers).
+Check for logical errors for function calls and Objective-C message expressions
+(e.g., uninitialized arguments, null function pointers).
+
+This checker is a collection of related checks that are controlled by checker
+options. The following checks are all enabled by default, but can be turned off
+by setting their option to ``false``:
+
+* **FunctionPointer** Check for null or undefined function pointer at function
+  call.
+* **CXXThisMethodCall** Check for null or undefined ``this`` pointer at method
+  call.
+* **CXXDeallocationArg** Check for null or undefined argument of
+  ``operator delete``.
+* **ArgInitializedness** Check for undefined pass-by-value function arguments.
+* **ParameterCount** Check for correct number of passed arguments to functions
+  or ObjC blocks. This will warn if the actual argument count is less (but not
+  if more) than the required count (by the declaration).
+* **NilReceiver** Check whether the receiver in a message expression is
+  ``nil``.
+* **UndefReceiver** Check whether the receiver in a message expression is
+  undefined.
+
+The following check is disabled by default (because it is more likely to
+produce false positives), this can be turned on by set the option to ``true``:
+
+* **ArgPointeeInitializedness** Check for undefined pass-by-reference (pointer
+  to constant value or constant reference) function arguments. In special cases
+  non-constant arguments are checked. This happens for C library functions
+  where it is required to initialize (at least partially) a passed structure
+  which is used for both input and output (for example last argument of
+  ``mktime`` or ``mbrlen``).
+
+**Additional options**
+
+* **ArgPointeeInitializednessComplete** Controls when to emit the warning at
+  the **ArgPointeeInitializedness** check. If this option is ``false`` (the
+  default), a ``struct`` is considered to be "initialized" when at least one
+  member is initialized. When this option is set to ``true``, structures are
+  only accepted as initialized when all members are initialized. (Arguments of
+  C library functions which require initialization are always checked as if the
+  option would be ``false``.)
+
+**Some examples**
 
 .. literalinclude:: checkers/callandmessage_example.c
     :language: objc