SCAN-BUILD(1)

πŸ’– SCAN-BUILD β€” Clang static analyzer πŸ’–

okay bestie, so this is the manual page for scan-build, from the General Commands Manual section of your local man collection. it's a whole vibe. let's get into it 🫢


✨ 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]

like. look at that. it's giving "I contain multitudes" πŸ’…


🌸 DESCRIPTION 🌸

so scan-build is a Perl script that invokes the Clang static analyzer. no cap, that's literally what it is.

the way it works: the options meant for scan-build or for the analyzer come first, and then after all that you put your build_command and any build_options β€” y'know, the normal stuff you'd type to build the target system. iconic.

the static analyzer runs a long list of checking algorithms β€” go look at β€œCHECKERS” below for the tea. and the output can be written in standard .plist and/or HTML format. your choice, main character πŸŽ€

The following options are supported:

  • -analyze-headers β€” also analyze functions in #included files. yes, the headers too. all of them. πŸ’–
  • -enable-checker checker_name, -disable-checker checker_name β€” turn checker_name on or off. go see β€œCHECKERS” for the full roster ✨
  • -h, --help β€” display this message. hi hello here it is πŸ‘‹
  • --help-checkers β€” list the default checkers, see β€œCHECKERS”.
  • --html-title[=*title*] β€” specify the title used on generated HTML pages. if you don't hand it a title, a default one gets generated for you. generous πŸ’…
  • -k, --keep-going β€” adds a β€œkeep on going” option to build_command. currently supports make and xcodebuild. this is a convenience option β€” you could honestly just specify this behavior directly using build options. either way, slay.
  • -o β€” target directory for the HTML report files. subdirectories get created as needed to represent separate invocations of the analyzer. if you don't specify this option, a directory is created in /tmp (TMPDIR on Mac OS X) to store the reports. it just. puts them somewhere. πŸ™ˆ
  • -plist β€” output the results as a set of .plist files. (by default the output of scan-build is a set of HTML files, fyi.)
  • -plist-html β€” output the results as a set of HTML and .plist files. both. why choose 🌈
  • --status-bugs β€” set exit status to 1 if it found potential bugs, and 0 otherwise. by default, the exit status of scan-build is whatever build_command returned.
  • --use-c++[=*compiler_path*] β€” guess the default compiler for your C++ and Objective-C++ code. use this option to specify an alternate compiler.
  • --use-cc[=*compiler_path*] β€” guess the default compiler for your C and Objective-C code. use this option to specify an alternate compiler.
  • -v β€” verbose output from scan-build and the analyzer. a second and third v increases verbosity. v. vv. vvv. escalating energy πŸ¦‹
  • -V, --view β€” view analysis results in a web browser when the build completes. ooh ahh ✨
  • -constraints [model] β€” specify the constraint engine used by the analyzer. by default the β€˜range’ model is used. specifying β€˜basic’ uses a simpler, less powerful constraint model β€” the one used by checker-0.160 and earlier. (so like, retro but make it weaker πŸ’€)
  • -maxloop N β€” specify the number of times a block can be visited before giving up. default is 4. increase it for more comprehensive coverage, at a cost of speed. more thorough = more waiting, that's the tradeoff bestie 😭
  • -no-failure-reports β€” do not create a β€˜failures’ subdirectory that includes analyzer crash reports and preprocessed source files.
  • -stats β€” generates visitation statistics for the project being analyzed. numbers!! ⭐
  • -store [model] β€” specify the store model used by the analyzer. by default, the β€˜region’ store model is used. β€˜region’ specifies a field-sensitive store model. you can also specify β€˜basic’, which is far less precise but can more quickly analyze code. β€˜basic’ was the default store model for checker-0.221 and earlier. throwback πŸŽ€

πŸ‘‘ EXIT STATUS πŸ‘‘

scan-build returns the value returned by build_command β€” unless --status-bugs or --keep-going is used. that's the whole rule, periodt.


🧚 CHECKERS 🧚

okay so all the checkers listed below can be enabled/disabled using the -enable-checker and -disable-checker options. a default group of checkers runs unless you explicitly disable them. exactly which checkers make up that default group is a function of the operating system in use β€” and you can see them listed with --help-checkers. iykyk πŸ’…

  • core.AdjustedReturnValue β€” 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 β€” check for null pointers passed as arguments to a function whose arguments are marked with the β€˜nonnull’ attribute.
  • core.CallAndMessage β€” check for logical errors for function calls and Objective-C message expressions (e.g., uninitialized arguments, null function pointers).
  • core.DivideZero β€” check for division by zero. 🚫
  • core.NullDereference β€” check for dereferences of null pointers.
  • core.StackAddressEscape β€” check that addresses to stack memory do not escape the function.
  • core.UndefinedBinaryOperatorResult β€” check for undefined results of binary operators.
  • core.VLASize β€” check for declarations of VLA of undefined or zero size.
  • core.builtin.BuiltinFunctions β€” evaluate compiler builtin functions, e.g. alloca().
  • core.builtin.NoReturnFunctions β€” evaluate β€˜panic’ functions that are known to not return to the caller.
  • core.uninitialized.ArraySubscript β€” check for uninitialized values used as array subscripts.
  • core.uninitialized.Assign β€” check for assigning uninitialized values.
  • core.uninitialized.Branch β€” check for uninitialized values used as branch conditions.
  • core.uninitialized.CapturedBlockVariable β€” check for blocks that capture uninitialized values.
  • core.uninitialized.UndefReturn β€” check for uninitialized values being returned to the caller.
  • deadcode.DeadStores β€” check for values stored to variables that are never read afterwards. rip to those assignments πŸ’€
  • debug.DumpCFG β€” display Control-Flow Graphs.
  • debug.DumpCallGraph β€” display Call Graph.
  • debug.DumpDominators β€” print the dominance tree for a given Control-Flow Graph.
  • debug.DumpLiveVars β€” print results of live variable analysis.
  • debug.Stats β€” emit warnings with analyzer statistics.
  • debug.TaintTest β€” mark tainted symbols as such.
  • debug.ViewCFG β€” view Control-Flow Graphs using GraphViz.
  • debug.ViewCallGraph β€” view Call Graph using GraphViz.
  • llvm.Conventions β€” check code for LLVM codebase conventions.
  • osx.API β€” check for proper uses of various Mac OS X APIs.
  • osx.AtomicCAS β€” evaluate calls to OSAtomic functions.
  • osx.SecKeychainAPI β€” check for proper uses of Secure Keychain APIs.
  • osx.cocoa.AtSync β€” check for null pointers used as mutexes for @synchronized.
  • osx.cocoa.ClassRelease β€” check for sending β€˜retain’, β€˜release,’ or β€˜autorelease’ directly to a Class.
  • osx.cocoa.IncompatibleMethodTypes β€” warn about Objective-C method signatures with type incompatibilities.
  • osx.cocoa.NSAutoreleasePool β€” warn for suboptimal uses of NSAutoreleasePool in Objective-C GC mode.
  • osx.cocoa.NSError β€” check usage of NSError** parameters.
  • osx.cocoa.NilArg β€” check for prohibited nil arguments to Objective-C method calls.
  • osx.cocoa.RetainCount β€” check for leaks and improper reference count management.
  • osx.cocoa.SelfInit β€” check that β€˜self’ is properly initialized inside an initializer method.
  • osx.cocoa.UnusedIvars β€” warn about private ivars that are never used.
  • osx.cocoa.VariadicMethodTypes β€” check for passing non-Objective-C types to variadic methods that expect only Objective-C types.
  • osx.coreFoundation.CFError β€” check usage of CFErrorRef* parameters.
  • osx.coreFoundation.CFNumber β€” check for proper uses of CFNumberCreate().
  • osx.coreFoundation.CFRetainRelease β€” check for null arguments to CFRetain(), CFRelease(), and CFMakeCollectable().
  • osx.coreFoundation.containers.OutOfBounds β€” checks for index out-of-bounds when using the CFArray API.
  • osx.coreFoundation.containers.PointerSizedValues β€” warns if CFArray, CFDictionary, or CFSet are created with non-pointer-size values.
  • security.FloatLoopCounter β€” warn on using a floating point value as a loop counter (CERT: FLP30-C, FLP30-CPP).
  • security.insecureAPI.UncheckedReturn β€” warn on uses of functions whose return values must be always checked.
  • security.insecureAPI.getpw β€” warn on uses of getpw().
  • security.insecureAPI.gets β€” warn on uses of gets().
  • security.insecureAPI.mkstemp β€” warn when mkstemp() is passed fewer than 6 X's in the format string.
  • security.insecureAPI.mktemp β€” warn on uses of mktemp().
  • security.insecureAPI.rand β€” warn on uses of rand(), random(), and related functions.
  • security.insecureAPI.strcpy β€” warn on uses of strcpy() and strcat().
  • security.insecureAPI.vfork β€” warn on uses of vfork().
  • unix.API β€” check calls to various UNIX/Posix functions.
  • unix.Malloc β€” check for memory leaks, double free, and use-after-free.
  • unix.cstring.BadSizeArg β€” check the size argument passed into C string functions for common erroneous patterns.
  • unix.cstring.NullArg β€” 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 runs make with the -j4 option. a different subdirectory is created each time scan-build analyzes a project. ✨

fr fr: the analyzer should support most parallel builds, but not distributed builds. know the limit bestie 😭

🫢 AUTHORS 🫢

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


okay that's the whole page, you ate it πŸ’… this was clang 14, dated Sep 29, 2021 β€” go forth and analyze, bestie πŸ¦‹πŸ’–

πŸ“¦ where this page comes from