Llvm-3.9.1 free download. GnuCOBOL (formerly OpenCOBOL) is a free, modern COBOL compiler. GnuCOBOL implements a substantial part of the COBOL 85, COBOL 2002 and COBOL 2014 standards and X/Open COBOL, as well as many extensions included in other COBOL compilers (IBM COBOL, MicroFocus COBOL, ACUCOBOL-GT and others). OS X Update version 10.9.2 brings XCode to version 5.1 (5B130a), and clang to the latest stable (for OS X): $ clang -version Apple LLVM version 5.1 (clang-503.0.38) (based on LLVM 3.4svn) Target: x8664-apple-darwin13.1.0 Thread model: posix On my Mac llvm-gcc and llvm-g are symlinks to this clang.
What is Static Analysis?
The term 'static analysis' is conflated, but here we use it to meana collection of algorithms and techniques used to analyze source code in orderto automatically find bugs. The idea is similar in spirit to compiler warnings(which can be useful for finding coding errors) but to take that idea a stepfurther and find bugs that are traditionally found using run-time debuggingtechniques such as testing.
Static analysis bug-finding tools have evolved over the last several decadesfrom basic syntactic checkers to those that find deep bugs by reasoning aboutthe semantics of code. The goal of the Clang Static Analyzer is to provide aindustrial-quality static analysis framework for analyzing C, C++, andObjective-C programs that is freely available, extensible, and has a high quality of implementation.
Part of Clang and LLVM
As its name implies, the Clang Static Analyzer is built on top of Clang and LLVM.Strictly speaking, the analyzer is part of Clang, as Clang consists of a set ofreusable C++ libraries for building powerful source-level tools. The staticanalysis engine used by the Clang Static Analyzer is a Clang library, and hasthe capability to be reused in different contexts and by different clients.
Important Points to Consider
While we believe that the static analyzer is already very useful for findingbugs, we ask you to bear in mind a few points when using it.
Work-in-Progress
The analyzer is a continuous work-in-progress. There are many plannedenhancements to improve both the precision and scope of its analysis algorithmsas well as the kinds of bugs it will find. While there are fundamentallimitations to what static analysis can do, we have a long way to go beforehitting that wall.
Slower than Compilation
Operationally, using static analysis toautomatically find deep program bugs is about trading CPU time for the hardeningof code. Because of the deep analysis performed by state-of-the-art staticanalysis tools, static analysis can be much slower than compilation.
While the Clang Static Analyzer is being designed to be as fast andlight-weight as possible, please do not expect it to be as fast as compiling aprogram (even with optimizations enabled). Some of the algorithms needed to findbugs require in the worst case exponential time.
The Clang Static Analyzer runs in a reasonable amount of time by bothbounding the amount of checking work it will do as well as using cleveralgorithms to reduce the amount of work it must do to find bugs.
False Positives
Static analysis is not perfect. It can falsely flag bugs in a program wherethe code behaves correctly. Because some code checks require more analysisprecision than others, the frequency of false positives can vary widely betweendifferent checks. Our long-term goal is to have the analyzer have a low falsepositive rate for most code on all checks.
Please help us in this endeavor by reporting falsepositives. False positives cannot be addressed unless we know aboutthem.
More Checks
Static analysis is not magic; a static analyzer can only find bugs that ithas been specifically engineered to find. If there are specific kinds of bugsyou would like the Clang Static Analyzer to find, please feel free tofile feature requests or contribute your ownpatches.
In this tutorial, you configure Visual Studio Code on macOS to use the Clang/LLVM compiler and debugger.
After configuring VS Code, you will compile and debug a simple C++ program in VS Code. This tutorial does not teach you about Clang or the C++ language. For those subjects, there are many good resources available on the Web.
If you have any trouble, feel free to file an issue for this tutorial in the VS Code documentation repository.
Prerequisites
To successfully complete this tutorial, you must do the following:
Ensure Clang is installed
Clang may already be installed on your Mac. To verify that it is, open a macOS Terminal window and enter the following command:
Create Hello World
From the macOS Terminal, create an empty folder called
projects where you can store all your VS Code projects, then create a subfolder called helloworld , navigate into it, and open VS Code in that folder by entering the following commands:
The
code . command opens VS Code in the current working folder, which becomes your 'workspace'. As you go through the tutorial, you will create three files in a .vscode folder in the workspace:
Add hello world source code file
In the File Explorer title bar, select New File and name the file
helloworld.cpp .
Paste in the following source code:
Now press ⌘S (Windows, Linux Ctrl+S) to save the file. Notice that your files are listed in the File Explorer view (⇧⌘E (Windows, Linux Ctrl+Shift+E)) in the side bar of VS Code:
You can also enable Auto Save to automatically save your file changes, by checking Auto Save in the main File menu.
The Activity Bar on the edge of Visual Studio Code lets you open different views such as Search, Source Control, and Run. You'll look at the Run view later in this tutorial. You can find out more about the other views in the VS Code User Interface documentation.
Note: When you save or open a C++ file, you may see a notification from the C/C++ extension about the availability of an Insiders version, which lets you test new features and fixes. You can ignore this notification by selecting the
X (Clear Notification).
Explore IntelliSense
In the
helloworld.cpp file, hover over vector or string to see type information. After the declaration of the msg variable, start typing msg. as you would when calling a member function. You should immediately see a completion list that shows all the member functions, and a window that shows the type information for the msg object:
You can press the Tab key to insert the selected member. Then, when you add the opening parenthesis, you'll see information about arguments that the function requires.
Build helloworld.cpp
Next, you'll create a
tasks.json file to tell VS Code how to build (compile) the program. This task will invoke the Clang C++ compiler to create an executable file from the source code.
It's important to have
helloworld.cpp open in the editor because the next step uses the active file in the editor as context to create the build task in the next step.
From the main menu, choose Terminal > Configure Default Build Task. A dropdown will appear listing various predefined build tasks for the compilers that VS Code found on your machine. Choose C/C++ clang++ build active file to build the file that is currently displayed (active) in the editor.
This will create a
tasks.json file in the .vscode folder and open it in the editor.
Replace the contents of that file with the following:
The JSON above differs from the default template JSON in the following ways:
The
command setting specifies the program to run. In this case, 'clang++' is the driver that causes the Clang compiler to expect C++ code and link against the C++ standard library.
The
args array specifies the command-line arguments that will be passed to clang++. These arguments must be specified in the order expected by the compiler.
This task tells the C++ compiler to compile the active file (
${file} ), and create an output file (-o switch) in the current directory (${fileDirname} ) with the same name as the active file (${fileBasenameNoExtension} ), resulting in helloworld for our example.
The
label value is what you will see in the tasks list. Name this whatever you like.
The
problemMatcher value selects the output parser to use for finding errors and warnings in the compiler output. For clang++, you'll get the best results if you use the $gcc problem matcher.
The
'isDefault': true value in the group object specifies that this task will be run when you press ⇧⌘B (Windows, Linux Ctrl+Shift+B). This property is for convenience only; if you set it to false , you can still build from the Terminal menu with Terminal > Run Build Task.
Note: You can learn more about
task.json variables in the variables reference.
Running the build
Modifying tasks.json
You can modify your
tasks.json to build multiple C++ files by using an argument like '${workspaceFolder}/*.cpp' instead of ${file} . This will build all .cpp files in your current folder. You can also modify the output filename by replacing '${fileDirname}/${fileBasenameNoExtension}' with a hard-coded filename (for example '${workspaceFolder}/myProgram.out' ).
Debug helloworld.cpp
Next, you'll create a
launch.json file to configure VS Code to launch the LLDB debugger when you press F5 to debug the program.
From the main menu, choose Run > Add Configuration.. and then choose C++ (GDB/LLDB).
You'll then see a dropdown for predefined debugging configurations. Choose clang++ build and debug active file.
VS Code creates a
launch.json file, opens it in the editor, and builds and runs 'helloworld'. Your launch.json file will look something like this:
The
program setting specifies the program you want to debug. Here it is set to the active file folder ${fileDirname} and active filename ${fileBasenameNoExtension} , which if helloworld.cpp is the active file will be helloworld .
By default, the C++ extension won't add any breakpoints to your source code and the
stopAtEntry value is set to false .
Change the
stopAtEntry value to true to cause the debugger to stop on the main method when you start debugging.
Ensure that the
preLaunchTask value matches the label of the build task in the task.json file.
Start a debugging session
Step through the code
Now you're ready to start stepping through the code.
Set a watch
You might want to keep track of the value of a variable as your program executes. You can do this by setting a watch Ubuntu 14.04 download for mac. on the variable.
C/C++ configuration
For more control over the C/C++ extension, create a
c_cpp_properties.json file, which allows you to change settings such as the path to the compiler, include paths, which C++ standard to compile against (such as C++17), and more.
View the C/C++ configuration UI by running the command C/C++: Edit Configurations (UI) from the Command Palette (⇧⌘P (Windows, Linux Ctrl+Shift+P)).
This opens the C/C++ Configurations page.
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Visual Studio Code places these settings in
.vscode/c_cpp_properties.json . If you open that file directly, it should look something like this:
You only need to modify the Include path setting if your program includes header files that are not in your workspace or the standard library path.
Compiler pathcompilerPath is an important configuration setting. The extension uses it to infer the path to the C++ standard library header files. When the extension knows where to find those files, it can provide useful features like smart completions and Go to Definition navigation.
The C/C++ extension attempts to populate
compilerPath with the default compiler location based on what it finds on your system. The compilerPath search order is:
Mac framework path
On the C/C++ Configuration screen, scroll down and expand Advanced Settings and ensure that Mac framework path points to the system header files. For example:
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks
Clang Llvm WindowsReusing your C++ configuration
VS Code is now configured to use Clang on macOS. The configuration applies to the current workspace. To reuse the configuration, just copy the JSON files to a
.vscode folder in a new project folder (workspace) and change the names of the source file(s) and executable as needed.
TroubleshootingCompiler and linking errors
The most common cause of errors (such as
undefined _main , or attempting to link with file built for unknown-unsupported file format , and so on) occurs when helloworld.cpp is not the active file when you start a build or start debugging. This is because the compiler is trying to compile something that isn't source code, like your launch.json , tasks.json , or c_cpp_properties.json file.
Next stepsClang Mac
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