Dr. Dobb's Journal - February 2008 - (Page 70)

d02mila_p5ma 12/7/07 3:30 PM Page 70 State of the Art STATICALLY TESTING C++ CODE A Static Testing Utility ==== Visual C++ test ==== Processing test file 'example.cpp' Running "cl /nologo /GX /Za /Ox /W4 /WX _test1.cpp 2>NUL >NUL" OK: Compilation with no errors nor warnings, as expected. Running "cl /nologo /GX /Za /Ox _test2.cpp 2>NUL >NUL" OK: Compilation with errors, as expected. Running "cl /nologo /GX /Za /Ox _test3.cpp 2>NUL >NUL" OK: Compilation with errors, as expected. Running "cl /nologo /GX /Za /Ox /W4 /WX _test4.cpp 2>NUL >NUL" Running "cl /nologo /GX /Za /Ox _test4.cpp 2>NUL >NUL" WARNING: Compilation with no errors but some warnings, while a compilation with no errors nor warnings was expected. Failures: 0, warnings: 1, successes: 3 One test file processed. Total failures: 0, total warnings: 1, total successes: 3. Figure 1: Execution output of the script for Windows. PC Presents Bug of the Month #661 -lint 8.0 for C/C++ #include #define N 5 int Weight[N] = { 3, 1, 4, 5, 2 }; A political party wishing to sabotage the chances of a popular presidential candidate, modifies the vote counting program to that shown. But something is not quite right. Can you spot the flaw? Visit our web site at www.gimpel.com int rand_choice() { int i, choice = 0; int k = rand() % (3*N); for( i = 0; i = 0 ) choice = i; k -= Weight[i]; } return choice; } int voting_machine( int vote ) { if( vote == 1 ) return rand_choice(); else return vote; } Plus Our Traditional C/C++ Warnings: Uninitialized variables, inherited non-virtual destructors, strong type mismatches,ill-formed macros, inadvertent name-hiding, suspicious expressions, etc., etc. Full Language Support for ANSI/ISO C and C++. PC-lint for C/C++ will catch this and many other bugs. It will analyze a mixed suite of C and C++ modules to uncover bugs, glitches, quirks and inconsistencies. Not your Grandpa’s lint: PC-lint has introduced several spectacular and revolutionary innovations in the art of static program analysis. Taking clues from initializers, assignments, and conditionals, variable and member values are tracked, enabling reports on potential uses of null pointers and out-of-bounds subscripts. New with Version 8: Interfunction value tracking – Actual argument values are used to initialize parameters; return values are computed; a multipass operation (you control the number of passes) allows you to plumb the depths of function behavior to arbitrary levels. PC-lint for C/C++ Numerous compilers/ libraries supported. Runs on Windows, MS-DOS, and OS/2. $239 FlexeLint for C/C++ The same great product for other operating systems. Runs on all UNIX systems, VMS, mainframes, etc. Distributed in shrouded C source form. Call for pricing. 30 Day Money Back Guarantee G i m p e l S o f t wa r e Serving the C/C++ Community for 22 Years. CALL TODAY (610) 584-4261 Or FAX (610) 584-4266 www.gimpel.com PC-lint and FlexeLint are trademarks of Gimpel Software 70 Dr. Dobb’s Journal l www.ddj.com l February 2008 I present here a utility that implements static testing automation. The utility is a standard C++ program that retrieves from the command line the paths of the files containing the static testing programs, and accesses some configuration environment variables. (The source code is available online; see “Resource Center,” page 5.) The program reads the files to process, and for each one (and for every marked snippet contained in the file), it generates a new source file whose syntactic correctness is then checked. To check the syntactic validity of a statement, the most efficient technique would be to use a library providing a compilation service or a static-analysis service. Such libraries do not exist for C++ (or they have little popularity). Alternatively, a compiler can be launched. If a compilation is successful, the process usually sets the return code to zero; if it fails, it sets the return code to another value. So, it is enough to execute the compiler, passing to it the desired options and the source code to check, wait for the completion of the compilation, and check the return code of the process. This is what this utility does. Some compilers allow an option that lets you perform only a syntax check on the code without generating the executable code, thereby speeding up the compilation. A further speedup can be obtained by disabling code optimization. Yet, some warnings are not output if a simple syntax check is performed or if code optimizations are disabled. Therefore, it is advisable to actually generate the optimized executable program, even if it is never executed. Additionally, there isn’t a standard technique to launch a compiler—every compiler has its incompatible options. Therefore, I put the dependencies from the compiler and the platform into environment variables. Included with the utility’s download package are two scripts—one for the Windows command interpreter (CMD.EXE) that tests the program with the Visual C++ and GCC compilers, and the other for UNIX/Linux shells that tests the same program with the GCC compiler. Figure 1 is the execution output of the script for Windows. DDJ l st ge y oo d. on sl e t kin e l uou ar an Th n tw m nti of . . co sed s of . ti ry ver to ad e his th in http://www.gimpel.com http://www.gimpel.com http://www.gimpel.com http://www.ddj.com

Table of Contents Feed for the Digital Edition of Dr. Dobb's Journal - February 2008

Dr. Dobb's Journal - February 2008 Contents Hmmmm Alia Vox Developer Diaries Developer’s Notebook South American Software Development Conversations Inside Visual Studio 2008 BibPort: Creating Bibliographic References Continuous LINQ The ZK Framework Static Testing C++ Code The Agile Edge Effective Concurrency Swaine’s Flames

Dr. Dobb's Journal - February 2008

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