[clang-tools-extra] [clang-tidy] Avoid checking magic numbers if _BitInt (PR #65888)

[via cfe-commits]

https://github.com/vabridgers created https://github.com/llvm/llvm-project/pull/65888:

Recent changes to add _BitInt support have caused our internal random testing to fail. This change just avoids a readability magic numbers check for now if a _BitInt. The crash seen (edited for clarity) is shown below.

<src-root>/llvm/include/llvm/ADT/APInt.h:1488:
  uint64_t llvm::APInt::getZExtValue() const: Assertion `getActiveBits()
  <= 64 && "Too many bits for uint64_t"' failed.

...
 #9 <address> llvm::APInt::getZExtValue() const
      <src-root>/llvm/include/llvm/ADT/APInt.h:1488:5
      clang::IntegerLiteral const*) const
      <src-root>/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.cpp:198:47
      <clang::IntegerLiteral>(clang::ast_matchers::MatchFinder::MatchResult
      const&, char const*)
      <src-root>/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.h:67:5
      clang::ast_matchers::MatchFinder::MatchResult const&)
      <src-root>/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.cpp:152:35
...

Reviewed By: donat.nagy

>From 9ecb065a60a67cef568b0c5d60c760a72e9bac93 Mon Sep 17 00:00:00 2001
From: Vince Bridgers <vince.a.bridgers at gmail.com>
Date: Sat, 9 Sep 2023 17:01:56 +0200
Subject: [PATCH] [clang-tidy] Avoid checking magic numbers if _BitInt

Recent changes to add _BitInt support have caused our internal random
testing to fail. This change just avoids a readability magic numbers
check for now if a _BitInt. The crash seen (edited for clarity) is shown
below.

<src-root>/llvm/include/llvm/ADT/APInt.h:1488:
  uint64_t llvm::APInt::getZExtValue() const: Assertion `getActiveBits()
  <= 64 && "Too many bits for uint64_t"' failed.

...
 #9 <address> llvm::APInt::getZExtValue() const
      <src-root>/llvm/include/llvm/ADT/APInt.h:1488:5
      clang::IntegerLiteral const*) const
      <src-root>/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.cpp:198:47
      <clang::IntegerLiteral>(clang::ast_matchers::MatchFinder::MatchResult
      const&, char const*)
      <src-root>/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.h:67:5
      clang::ast_matchers::MatchFinder::MatchResult const&)
      <src-root>/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.cpp:152:35
...

Reviewed By: donat.nagy
---
 .../clang-tidy/readability/MagicNumbersCheck.cpp            | 3 +++
 .../test/clang-tidy/checkers/readability/bitint-no-crash.c  | 6 ++++++
 2 files changed, 9 insertions(+)
 create mode 100644 clang-tools-extra/test/clang-tidy/checkers/readability/bitint-no-crash.c

diff --git a/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.cpp b/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.cpp
index 7f3c2cb9a0434cc..97c20cf200fa21c 100644
--- a/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.cpp
+++ b/clang-tools-extra/clang-tidy/readability/MagicNumbersCheck.cpp
@@ -191,6 +191,9 @@ bool MagicNumbersCheck::isConstant(const MatchFinder::MatchResult &Result,
 }
 
 bool MagicNumbersCheck::isIgnoredValue(const IntegerLiteral *Literal) const {
+  if (Literal->getType()->isBitIntType()) {
+    return true;
+  }
   const llvm::APInt IntValue = Literal->getValue();
   const int64_t Value = IntValue.getZExtValue();
   if (Value == 0)
diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/bitint-no-crash.c b/clang-tools-extra/test/clang-tidy/checkers/readability/bitint-no-crash.c
new file mode 100644
index 000000000000000..f8660924cbef5a0
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/readability/bitint-no-crash.c
@@ -0,0 +1,6 @@
+// RUN: %check_clang_tidy %s readability-magic-numbers %t --
+
+// Don't crash
+
+_BitInt(128) A = 4533629751480627964421wb;
+// CHECK-MESSAGES: warning