SCAN-BUILD(1)

NAME
scan-build - Clang static analyzer

SYNOPSIS
scan-build [-ohkvV] [-analyze-headers] [-enable-checker [checker_name]] [-disable-checker [checker_name]] [- -help] [- -help-checkers] [- -html-title [=title]] [- -keep-going] [-plist] [-plist-html] [- -status-bugs] [- -use-c++ [=compiler_path]] [- -use-cc [=compiler_path]] [- -view] [-constraints [model]] [-maxloop N] [-no-failure-reports] [-stats] [-store [model]] build_command [build_options]

DESCRIPTION
scan-build is a Perl script that invokes the Clang static analyzer. Options used by scan-build or by the analyzer appear first, followed by the build_command and any build_options normally used to build the target system.

The static analyzer employs a long list of checking algorithms, see CHECKERS. Output can be written in standard .plist and/or HTML format.

The following options are supported:

-analyze-headers
    Also analyze functions in #included files.

-enable-checker checker_name, -disable-checker checker_name
    Enable/disable checker_name. See CHECKERS.

-h, - -help
    Display this message.

- -help-checkers
    List default checkers, see CHECKERS.

- -html-title[=title]
    Specify the title used on generated HTML pages. A default title is generated if title is not specified.

-k, - -keep-going
    Add a “keep on going” option to build_command. Currently supports make and xcodebuild. This is a convenience option; one can specify this behavior directly using build options.

-o  Target directory for HTML report files. Subdirectories will be created as needed to represent separate invocations of the analyzer. If this option is not specified, a directory is created in /tmp (TMPDIR on Mac OS X) to store the reports.

-plist
    Output the results as a set of .plist files. (By default the output of scan-build is a set of HTML files.)

-plist-html
    Output the results as a set of HTML and .plist files

- -status-bugs
    Set exit status to 1 if it found potential bugs and 0 otherwise. By default the exit status of scan-build is that returned by build_command.

- -use-c++[=compiler_path]
    Guess the default compiler for your C++ and Objective-C++ code. Use this option to specify an alternate compiler.

- -use-cc[=compiler_path]
    Guess the default compiler for your C and Objective-C code. Use this option to specify an alternate compiler.

-v  Verbose output from scan-build and the analyzer. A second and third v increases verbosity.

-V, - -view
    View analysis results in a web browser when the build completes.

-constraints [model]
    Specify the contraint engine used by the analyzer. By default the ‘range’ model is used. Specifying ‘basic’ uses a simpler, less powerful constraint model used by checker-0.160 and earlier.

-maxloop N
    Specifiy the number of times a block can be visited before giving up. Default is 4. Increase for more comprehensive coverage at a cost of speed.

-no-failure-reports
    Do not create a ‘failures’ subdirectory that includes analyzer crash reports and preprocessed source files.

-stats
    Generates visitation statistics for the project being analyzed.

-store [model]
    Specify the store model used by the analyzer. By default, the ‘region’ store model is used. ‘region’ specifies a field- sensitive store model. Users can also specify ‘basic’ which is far less precise but can more quickly analyze code. ‘basic’ was the default store model for checker-0.221 and earlier.

RETURN VALUES
scan-build returns the value returned by build_command unless - -status-bugs or - -keep-going is used.

CHECKERS
The checkers listed below may be enabled/disabled using the -enable-checker and -disable-checker options. A default group of checkers is run unless explicitly disabled. Exactly which checkers constitute the default group is a function of the operating system in use; they are listed with - -help-checkers.

core.AdjustedReturnValue
    Check to see if the return value of a function call is different than the caller expects (e.g., from calls through function pointers).

core.AttributeNonNull
    Check for null pointers passed as arguments to a function whose arguments are marked with the ‘nonnull’ attribute.

core.CallAndMessage
    Check for logical errors for function calls and Objective-C message expressions (e.g., uninitialized arguments, null function pointers).

core.DivideZero
    Check for division by zero.

core.NullDereference
    Check for dereferences of null pointers.

core.StackAddressEscape
    Check that addresses to stack memory do not escape the function.

core.UndefinedBinaryOperatorResult
    Check for undefined results of binary operators.

core.VLASize
    Check for declarations of VLA of undefined or zero size.

core.builtin.BuiltinFunctions
    Evaluate compiler builtin functions, e.g. alloca().

core.builtin.NoReturnFunctions
    Evaluate ‘panic’ functions that are known to not return to the caller.

core.uninitialized.ArraySubscript
    Check for uninitialized values used as array subscripts.

core.uninitialized.Assign
    Check for assigning uninitialized values.

core.uninitialized.Branch
    Check for uninitialized values used as branch conditions.

core.uninitialized.CapturedBlockVariable
    Check for blocks that capture uninitialized values.

core.uninitialized.UndefReturn
    Check for uninitialized values being returned to the caller.

deadcode.DeadStores
    Check for values stored to variables that are never read afterwards.

debug.DumpCFG
    Display Control-Flow Graphs.

debug.DumpCallGraph
    Display Call Graph.

debug.DumpDominators
    Print the dominance tree for a given Control-Flow Graph.

debug.DumpLiveVars
    Print results of live variable analysis.

debug.Stats
    Emit warnings with analyzer statistics.

debug.TaintTest
    Mark tainted symbols as such.

debug.ViewCFG
    View Control-Flow Graphs using GraphViz.

debug.ViewCallGraph
    View Call Graph using GraphViz.

llvm.Conventions
    Check code for LLVM codebase conventions.

osx.API
    Check for proper uses of various Mac OS X APIs.

osx.AtomicCAS
    Evaluate calls to OSAtomic functions.

osx.SecKeychainAPI
    Check for proper uses of Secure Keychain APIs.

osx.cocoa.AtSync
    Check for null pointers used as mutexes for @synchronized.

osx.cocoa.ClassRelease
    Check for sending ‘retain’, ‘release,’ or ‘autorelease’ directly to a Class.

osx.cocoa.IncompatibleMethodTypes
    Warn about Objective-C method signatures with type incompatibilities.

osx.cocoa.NSAutoreleasePool
    Warn for suboptimal uses of NSAutoreleasePool in Objective-C GC mode.

osx.cocoa.NSError
    Check usage of NSError** parameters.

osx.cocoa.NilArg
    Check for prohibited nil arguments to Objective-C method calls.

osx.cocoa.RetainCount
    Check for leaks and improper reference count management.

osx.cocoa.SelfInit
    Check that ‘self’ is properly initialized inside an initializer method.

osx.cocoa.UnusedIvars
    Warn about private ivars that are never used.

osx.cocoa.VariadicMethodTypes
    Check for passing non-Objective-C types to variadic methods that expect only Objective-C types.

osx.coreFoundation.CFError
    Check usage of CFErrorRef* parameters.

osx.coreFoundation.CFNumber
    Check for proper uses of CFNumberCreate().

osx.coreFoundation.CFRetainRelease
    Check for null arguments to CFRetain() and CFRelease().

osx.coreFoundation.containers.OutOfBounds
    Checks for index out-of-bounds when using the CFArray API.

osx.coreFoundation.containers.PointerSizedValues
    Warns if CFArray, CFDictionary, or CFSet are created with non-pointer-size values.

security.FloatLoopCounter
    Warn on using a floating point value as a loop counter (CERT: FLP30-C, FLP30-CPP).

security.insecureAPI.UncheckedReturn
    Warn on uses of functions whose return values must be always checked.

security.insecureAPI.getpw
    Warn on uses of getpw().

security.insecureAPI.gets
    Warn on uses of gets().

security.insecureAPI.mkstemp
    Warn when mkstemp() is passed fewer than 6 X's in the format string.

security.insecureAPI.mktemp
    Warn on uses of mktemp().

security.insecureAPI.rand
    Warn on uses of rand(), random(), and related functions.

security.insecureAPI.strcpy
    Warn on uses of strcpy() and strcat().

security.insecureAPI.vfork
    Warn on uses of vfork().

unix.API
    Check calls to various UNIX/Posix functions.

unix.Malloc
    Check for memory leaks, double free, and use-after-free.

unix.cstring.BadSizeArg
    Check the size argument passed into C string functions for common erroneous patterns.

unix.cstring.NullArg
    Check for null pointers being passed as arguments to C string functions.

EXAMPLE
scan-build -o /tmp/myhtmldir make -j4

The above example causes analysis reports to be deposited into a subdirectory of /tmp/myhtmldir and to run make with the -j4 option. A different subdirectory is created each time scan-build analyzes a project. The analyzer should support most parallel builds, but not distributed builds.

AUTHORS
scan-build was written by Ted Kremenek. Documentation contributed by James K. Lowden <jklowden@schemamania.org>.