[Analyzer] More accurate modeling about the increment operator of the operand with type bool.
Summary:
There is a problem with analyzer that a wrong value is given when modeling the increment operator of the operand with type bool. After `rL307604` is applied, a unsigned overflow may occur.
Example:
```
void func() {
bool b = true;
// unsigned overflow occur, 2 -> 0 U1b
b++;
}
```
The use of an operand of type bool with the ++ operators is deprecated but valid untill C++17. And if the operand of the increment operator is of type bool, it is set to true.
This patch includes two parts:
- If the operand of the increment operator is of type bool or type _Bool, set to true.
- Modify `BasicValueFactory::getTruthValue()`, use `getIntWidth()` instead `getTypeSize()` and use `unsigned` instead `signed`.
Reviewers: alexshap, NoQ, dcoughlin, george.karpenkov
Reviewed By: NoQ
Subscribers: xazax.hun, szepet, a.sidorin, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D43741
llvm-svn: 326776
diff --git a/clang/test/Analysis/bool-increment.cpp b/clang/test/Analysis/bool-increment.cpp
new file mode 100644
index 0000000..93002d3
--- /dev/null
+++ b/clang/test/Analysis/bool-increment.cpp
@@ -0,0 +1,84 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=debug.ExprInspection -verify -std=c++98 -Wno-deprecated %s
+// RUN: %clang_analyze_cc1 -analyzer-checker=debug.ExprInspection -verify -std=c++11 -Wno-deprecated %s
+// RUN: %clang_analyze_cc1 -analyzer-checker=debug.ExprInspection -verify -std=c++14 -Wno-deprecated %s
+
+extern void clang_analyzer_eval(bool);
+
+void test_bool_value() {
+ {
+ bool b = true;
+ clang_analyzer_eval(b == 1); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = false;
+ clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = -10;
+ clang_analyzer_eval(b == 1); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = 10;
+ clang_analyzer_eval(b == 1); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = 10;
+ b++;
+ clang_analyzer_eval(b == 1); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = 0;
+ b++;
+ clang_analyzer_eval(b == 1); // expected-warning{{TRUE}}
+ }
+}
+
+void test_bool_increment() {
+ {
+ bool b = true;
+ b++;
+ clang_analyzer_eval(b); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = false;
+ b++;
+ clang_analyzer_eval(b); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = true;
+ ++b;
+ clang_analyzer_eval(b); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = false;
+ ++b;
+ clang_analyzer_eval(b); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = 0;
+ ++b;
+ clang_analyzer_eval(b); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = 10;
+ ++b;
+ ++b;
+ clang_analyzer_eval(b); // expected-warning{{TRUE}}
+ }
+
+ {
+ bool b = -10;
+ ++b;
+ clang_analyzer_eval(b); // expected-warning{{TRUE}}
+ }
+}