[clang] [analyzer] EnumCastOutOfRangeChecker: report the value (PR #74503)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: None (DonatNagyE)

<details>
<summary>Changes</summary>

...that is causing the bug report when it's converted to the enum type. This commit only improves the diagnostics and does not affect the set of reports.

---

Patch is 26.77 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/74503.diff


2 Files Affected:

- (modified) clang/lib/StaticAnalyzer/Checkers/EnumCastOutOfRangeChecker.cpp (+16-9) 
- (modified) clang/test/Analysis/enum-cast-out-of-range.cpp (+50-50) 


``````````diff
diff --git a/clang/lib/StaticAnalyzer/Checkers/EnumCastOutOfRangeChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/EnumCastOutOfRangeChecker.cpp
index 5844f43991001..14433d06c2d04 100644
--- a/clang/lib/StaticAnalyzer/Checkers/EnumCastOutOfRangeChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/EnumCastOutOfRangeChecker.cpp
@@ -22,10 +22,12 @@
 #include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "llvm/Support/FormatVariadic.h"
 #include <optional>
 
 using namespace clang;
 using namespace ento;
+using llvm::formatv;
 
 namespace {
 // This evaluator checks two SVals for equality. The first SVal is provided via
@@ -87,17 +89,22 @@ void EnumCastOutOfRangeChecker::reportWarning(CheckerContext &C,
       EnumValueCastOutOfRange.reset(
           new BugType(this, "Enum cast out of range"));
 
-    llvm::SmallString<128> Msg{"The value provided to the cast expression is "
-                               "not in the valid range of values for "};
-    StringRef EnumName{E->getName()};
-    if (EnumName.empty()) {
-      Msg += "the enum";
-    } else {
-      Msg += '\'';
-      Msg += EnumName;
-      Msg += '\'';
+    std::string ValueStr = "", NameStr = "the enum";
+
+    // Try to add details to the message:
+    const auto ConcreteValue =
+        C.getSVal(CE->getSubExpr()).getAs<nonloc::ConcreteInt>();
+    if (ConcreteValue) {
+      ValueStr = formatv(" '{0}'", ConcreteValue->getValue());
+    }
+    if (StringRef EnumName{E->getName()}; !EnumName.empty()) {
+      NameStr = formatv("'{0}'", EnumName);
     }
 
+    std::string Msg = formatv("The value{0} provided to the cast expression is "
+                              "not in the valid range of values for {1}",
+                              ValueStr, NameStr);
+
     auto BR = std::make_unique<PathSensitiveBugReport>(*EnumValueCastOutOfRange,
                                                        Msg, N);
     bugreporter::trackExpressionValue(N, CE->getSubExpr(), *BR);
diff --git a/clang/test/Analysis/enum-cast-out-of-range.cpp b/clang/test/Analysis/enum-cast-out-of-range.cpp
index 0eb740664ecdc..09835d420672b 100644
--- a/clang/test/Analysis/enum-cast-out-of-range.cpp
+++ b/clang/test/Analysis/enum-cast-out-of-range.cpp
@@ -43,115 +43,115 @@ struct S {
 };
 
 void unscopedUnspecified() {
-  unscoped_unspecified_t InvalidBeforeRangeBegin = static_cast<unscoped_unspecified_t>(-5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidBeforeRangeBegin = static_cast<unscoped_unspecified_t>(-5); // expected-warning {{The value '-5' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
   unscoped_unspecified_t ValidNegativeValue1 = static_cast<unscoped_unspecified_t>(-4); // OK.
   unscoped_unspecified_t ValidNegativeValue2 = static_cast<unscoped_unspecified_t>(-3); // OK.
-  unscoped_unspecified_t InvalidInsideRange1 = static_cast<unscoped_unspecified_t>(-2); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
-  unscoped_unspecified_t InvalidInsideRange2 = static_cast<unscoped_unspecified_t>(-1); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
-  unscoped_unspecified_t InvalidInsideRange3 = static_cast<unscoped_unspecified_t>(0); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidInsideRange1 = static_cast<unscoped_unspecified_t>(-2); // expected-warning {{The value '-2' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidInsideRange2 = static_cast<unscoped_unspecified_t>(-1); // expected-warning {{The value '-1' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidInsideRange3 = static_cast<unscoped_unspecified_t>(0); // expected-warning {{The value '0' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
   unscoped_unspecified_t ValidPositiveValue1 = static_cast<unscoped_unspecified_t>(1); // OK.
   unscoped_unspecified_t ValidPositiveValue2 = static_cast<unscoped_unspecified_t>(2); // OK.
-  unscoped_unspecified_t InvalidInsideRange4 = static_cast<unscoped_unspecified_t>(3); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidInsideRange4 = static_cast<unscoped_unspecified_t>(3); // expected-warning {{The value '3' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
   unscoped_unspecified_t ValidPositiveValue3 = static_cast<unscoped_unspecified_t>(4); // OK.
-  unscoped_unspecified_t InvalidAfterRangeEnd = static_cast<unscoped_unspecified_t>(5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidAfterRangeEnd = static_cast<unscoped_unspecified_t>(5); // expected-warning {{The value '5' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
 }
 
 void unscopedSpecified() {
-  unscoped_specified_t InvalidBeforeRangeBegin = static_cast<unscoped_specified_t>(-5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidBeforeRangeBegin = static_cast<unscoped_specified_t>(-5); // expected-warning {{The value '-5' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
   unscoped_specified_t ValidNegativeValue1 = static_cast<unscoped_specified_t>(-4); // OK.
   unscoped_specified_t ValidNegativeValue2 = static_cast<unscoped_specified_t>(-3); // OK.
-  unscoped_specified_t InvalidInsideRange1 = static_cast<unscoped_specified_t>(-2); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
-  unscoped_specified_t InvalidInsideRange2 = static_cast<unscoped_specified_t>(-1); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
-  unscoped_specified_t InvalidInsideRange3 = static_cast<unscoped_specified_t>(0); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidInsideRange1 = static_cast<unscoped_specified_t>(-2); // expected-warning {{The value '-2' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidInsideRange2 = static_cast<unscoped_specified_t>(-1); // expected-warning {{The value '-1' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidInsideRange3 = static_cast<unscoped_specified_t>(0); // expected-warning {{The value '0' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
   unscoped_specified_t ValidPositiveValue1 = static_cast<unscoped_specified_t>(1); // OK.
   unscoped_specified_t ValidPositiveValue2 = static_cast<unscoped_specified_t>(2); // OK.
-  unscoped_specified_t InvalidInsideRange4 = static_cast<unscoped_specified_t>(3); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidInsideRange4 = static_cast<unscoped_specified_t>(3); // expected-warning {{The value '3' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
   unscoped_specified_t ValidPositiveValue3 = static_cast<unscoped_specified_t>(4); // OK.
-  unscoped_specified_t InvalidAfterRangeEnd = static_cast<unscoped_specified_t>(5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidAfterRangeEnd = static_cast<unscoped_specified_t>(5); // expected-warning {{The value '5' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
 }
 
 void scopedUnspecified() {
-  scoped_unspecified_t InvalidBeforeRangeBegin = static_cast<scoped_unspecified_t>(-5); // expected-warning{{The value provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
+  scoped_unspecified_t InvalidBeforeRangeBegin = static_cast<scoped_unspecified_t>(-5); // expected-warning{{The value '-5' provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
   scoped_unspecified_t ValidNegativeValue1 = static_cast<scoped_unspecified_t>(-4); // OK.
   scoped_unspecified_t ValidNegativeValue2 = static_cast<scoped_unspecified_t>(-3); // OK.
-  scoped_unspecified_t InvalidInsideRange1 = static_cast<scoped_unspecified_t>(-2); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
-  scoped_unspecified_t InvalidInsideRange2 = static_cast<scoped_unspecified_t>(-1); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
-  scoped_unspecified_t InvalidInsideRange3 = static_cast<scoped_unspecified_t>(0); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
+  scoped_unspecified_t InvalidInsideRange1 = static_cast<scoped_unspecified_t>(-2); // expected-warning {{The value '-2' provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
+  scoped_unspecified_t InvalidInsideRange2 = static_cast<scoped_unspecified_t>(-1); // expected-warning {{The value '-1' provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
+  scoped_unspecified_t InvalidInsideRange3 = static_cast<scoped_unspecified_t>(0); // expected-warning {{The value '0' provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
   scoped_unspecified_t ValidPositiveValue1 = static_cast<scoped_unspecified_t>(1); // OK.
   scoped_unspecified_t ValidPositiveValue2 = static_cast<scoped_unspecified_t>(2); // OK.
-  scoped_unspecified_t InvalidInsideRange4 = static_cast<scoped_unspecified_t>(3); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
+  scoped_unspecified_t InvalidInsideRange4 = static_cast<scoped_unspecified_t>(3); // expected-warning {{The value '3' provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
   scoped_unspecified_t ValidPositiveValue3 = static_cast<scoped_unspecified_t>(4); // OK.
-  scoped_unspecified_t InvalidAfterRangeEnd = static_cast<scoped_unspecified_t>(5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
+  scoped_unspecified_t InvalidAfterRangeEnd = static_cast<scoped_unspecified_t>(5); // expected-warning {{The value '5' provided to the cast expression is not in the valid range of values for 'scoped_unspecified_t'}}
 }
 
 void scopedSpecified() {
-  scoped_specified_t InvalidBeforeRangeBegin = static_cast<scoped_specified_t>(-5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
+  scoped_specified_t InvalidBeforeRangeBegin = static_cast<scoped_specified_t>(-5); // expected-warning {{The value '-5' provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
   scoped_specified_t ValidNegativeValue1 = static_cast<scoped_specified_t>(-4); // OK.
   scoped_specified_t ValidNegativeValue2 = static_cast<scoped_specified_t>(-3); // OK.
-  scoped_specified_t InvalidInsideRange1 = static_cast<scoped_specified_t>(-2); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
-  scoped_specified_t InvalidInsideRange2 = static_cast<scoped_specified_t>(-1); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
-  scoped_specified_t InvalidInsideRange3 = static_cast<scoped_specified_t>(0); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
+  scoped_specified_t InvalidInsideRange1 = static_cast<scoped_specified_t>(-2); // expected-warning {{The value '-2' provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
+  scoped_specified_t InvalidInsideRange2 = static_cast<scoped_specified_t>(-1); // expected-warning {{The value '-1' provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
+  scoped_specified_t InvalidInsideRange3 = static_cast<scoped_specified_t>(0); // expected-warning {{The value '0' provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
   scoped_specified_t ValidPositiveValue1 = static_cast<scoped_specified_t>(1); // OK.
   scoped_specified_t ValidPositiveValue2 = static_cast<scoped_specified_t>(2); // OK.
-  scoped_specified_t InvalidInsideRange4 = static_cast<scoped_specified_t>(3); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
+  scoped_specified_t InvalidInsideRange4 = static_cast<scoped_specified_t>(3); // expected-warning {{The value '3' provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
   scoped_specified_t ValidPositiveValue3 = static_cast<scoped_specified_t>(4); // OK.
-  scoped_specified_t InvalidAfterRangeEnd = static_cast<scoped_specified_t>(5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
+  scoped_specified_t InvalidAfterRangeEnd = static_cast<scoped_specified_t>(5); // expected-warning {{The value '5' provided to the cast expression is not in the valid range of values for 'scoped_specified_t'}}
 }
 
 void unscopedUnspecifiedCStyle() {
-  unscoped_unspecified_t InvalidBeforeRangeBegin = (unscoped_unspecified_t)(-5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidBeforeRangeBegin = (unscoped_unspecified_t)(-5); // expected-warning {{The value '-5' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
   unscoped_unspecified_t ValidNegativeValue1 = (unscoped_unspecified_t)(-4); // OK.
   unscoped_unspecified_t ValidNegativeValue2 = (unscoped_unspecified_t)(-3); // OK.
-  unscoped_unspecified_t InvalidInsideRange1 = (unscoped_unspecified_t)(-2); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
-  unscoped_unspecified_t InvalidInsideRange2 = (unscoped_unspecified_t)(-1); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
-  unscoped_unspecified_t InvalidInsideRange3 = (unscoped_unspecified_t)(0); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidInsideRange1 = (unscoped_unspecified_t)(-2); // expected-warning {{The value '-2' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidInsideRange2 = (unscoped_unspecified_t)(-1); // expected-warning {{The value '-1' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidInsideRange3 = (unscoped_unspecified_t)(0); // expected-warning {{The value '0' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
   unscoped_unspecified_t ValidPositiveValue1 = (unscoped_unspecified_t)(1); // OK.
   unscoped_unspecified_t ValidPositiveValue2 = (unscoped_unspecified_t)(2); // OK.
-  unscoped_unspecified_t InvalidInsideRange4 = (unscoped_unspecified_t)(3); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidInsideRange4 = (unscoped_unspecified_t)(3); // expected-warning {{The value '3' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
   unscoped_unspecified_t ValidPositiveValue3 = (unscoped_unspecified_t)(4); // OK.
-  unscoped_unspecified_t InvalidAfterRangeEnd = (unscoped_unspecified_t)(5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
+  unscoped_unspecified_t InvalidAfterRangeEnd = (unscoped_unspecified_t)(5); // expected-warning {{The value '5' provided to the cast expression is not in the valid range of values for 'unscoped_unspecified_t'}}
 }
 
 void unscopedSpecifiedCStyle() {
-  unscoped_specified_t InvalidBeforeRangeBegin = (unscoped_specified_t)(-5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidBeforeRangeBegin = (unscoped_specified_t)(-5); // expected-warning {{The value '-5' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
   unscoped_specified_t ValidNegativeValue1 = (unscoped_specified_t)(-4); // OK.
   unscoped_specified_t ValidNegativeValue2 = (unscoped_specified_t)(-3); // OK.
-  unscoped_specified_t InvalidInsideRange1 = (unscoped_specified_t)(-2); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
-  unscoped_specified_t InvalidInsideRange2 = (unscoped_specified_t)(-1); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
-  unscoped_specified_t InvalidInsideRange3 = (unscoped_specified_t)(0); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidInsideRange1 = (unscoped_specified_t)(-2); // expected-warning {{The value '-2' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidInsideRange2 = (unscoped_specified_t)(-1); // expected-warning {{The value '-1' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidInsideRange3 = (unscoped_specified_t)(0); // expected-warning {{The value '0' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
   unscoped_specified_t ValidPositiveValue1 = (unscoped_specified_t)(1); // OK.
   unscoped_specified_t ValidPositiveValue2 = (unscoped_specified_t)(2); // OK.
-  unscoped_specified_t InvalidInsideRange4 = (unscoped_specified_t)(3); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_specified_t InvalidInsideRange4 = (unscoped_specified_t)(3); // expected-warning {{The value '3' provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
   unscoped_specified_t ValidPositiveValue3 = (unscoped_specified_t)(4); // OK.
-  unscoped_specified_t InvalidAfterRangeEnd = (unscoped_specified_t)(5); // expected-warning {{The value provided to the cast expression is not in the valid range of values for 'unscoped_specified_t'}}
+  unscoped_s...
[truncated]

``````````

</details>


https://github.com/llvm/llvm-project/pull/74503