Good compiler warnings can prevent software bugs from the beginning on. Sadly, most warnings are either undetected or disabled by the default warning level. This repo checks the warning coverage of popular C++ compilers against 70 test cases in the 📂src subfolder.
Make sure a C++ compiler and cmake is installed. Then execute in a terminal window:
> git clone https://github.com/fleschutz/CWTS # or download and unzip the ZIP file (click the green button)
> cd CWTS/src
> cmake . # edit 'CMakeLists.txt' before to select a certain C++ compiler
> make -k # option '-k' means keep going, even on errors
Each test case compiled without a warning or error counts as a miss (👎). And the winner is:
- clang-tidy 20.1.8 which misses 2 only
- Visual Studio 2019 misses 17
- Visual Studio 2017 misses 19
- Clang 20.1.8 misses 24
- GCC 15.2.0 misses 32
- Cppcheck 2.17.1 misses 32
Note: All test results based on highest warning level. See 📂test_results for details (including older versions).
No, compilers don't enable the highest warning level by default. All have a default warning level of 'normal', far from highest level. And each one supports different options to be more pedantic:
| Compiler | Options | Comment |
|---|---|---|
| Clang | -Weverything -pedantic |
|
| clang-tidy | -checks=*,-modernize* |
all checks except 'modernize' hints |
| Cppcheck | --enable=all |
|
| GCC | -Wall -Wextra -pedantic -Wundef |
-Wall and -Wextra do not enable all warnings! To keep backwards compatibility, -Wall is basically, "All warnings as of 1990." -Wextra covers a lot of the newer warnings, but still misses a few. |
| Visual Studio | /Wall |
good job, no bla bla 👌 |
It means a project is compiled with the highest warning level and zero compiler warnings are acceptable.
Introducing the Zero Warnings Policy by enabling the highest warning level often results in hundreds or thousands of warnings. To get started you may want to begin with a lower warning level first. Then fix those warnings and gradually dial up the warning level.
As soon as there are no more warnings turn warnings into errors to enforce the Zero Warnings Policy from now on. That way warnings can no longer be ignored because the build fails. The corresponding compiler options are -Werror for Clang and GCC and /WX for Visual Studio.
- Contributions, suggestions, and improvements are welcome!
- Open an Issue if you encounter bugs or have feature ideas.
- Create a Pull Request if you'd like to improve something.
This open source project is licensed under the CC0 license. All trademarks are the property of their respective owners.