[cfe-dev] unclear about how to correctly run scan-build through make

[Jordan Rose]

scan-build works by substituting a dummy CC and CXX to interpose on your build system. Your makefile needs to either use these variables, or you need to reconfigure through scan-build. From http://clang-analyzer.llvm.org/scan-build.html:

> The reason configure also needs to be run through scan-build is because scan-build scans your source files by interposing on the compiler. This interposition is currently done by scan-build temporarily setting the environment variable CC to ccc-analyzer. The program ccc-analyzer acts like a fake compiler, forwarding its command line arguments over to the compiler to perform regular compilation and clang to perform static analysis.
> 

By default, scan-build will use GCC to compile things on non-Darwin platforms. To override this, you can use the --use-cc and --use-c++ options (same as --use-analyzer).

Does that fix your problem?
Jordan


On Dec 12, 2012, at 10:17 , Peeter Joot <peeter.joot at gmail.com> wrote:

> If I run scan-build on one file manually I get a report directory created as expected:
> 
> # cat t.C
> int * foo(){ int x ; return &x ;}
> 
> # scan-build -o $HOME/scan-build --use-analyzer=`which clang` clang++ t.C -c
> scan-build: Using '/home/peeterj/clang/optimized/bin/clang' for static analysis
> t.C:1:30: warning: address of stack memory associated with local variable 'x' returned [-Wreturn-stack-address]
> int * foo(){ int x ; return &x ;}
>                              ^
> 1 warning generated.
> t.C:1:22: warning: Address of stack memory associated with local variable 'x' returned to caller
> int * foo(){ int x ; return &x ;}
>              ~~~~~   ^      ~~
> 1 warning generated.
> scan-build: 1 bugs found.
> scan-build: Run 'scan-view /home/peeterj/scan-build/2012-12-12-3' to examine bug reports.
> 
> However, if I run this using a make rule, I see scan-build invoke make, but get the "contains no reports" message:
> 
> # rm *.o
> # cat makefile
> t.o : t.C
>         clang++ t.C -c
> # scan-build -o $HOME/scan-build --use-analyzer=`which clang` make
> scan-build: Using '/home/peeterj/clang/optimized/bin/clang' for static analysis
> clang++ t.C -c
> t.C:1:30: warning: address of stack memory associated with local variable 'x' returned [-Wreturn-stack-address]
> int * foo(){ int x ; return &x ;}
>                              ^
> 1 warning generated.
> scan-build: Removing directory '/home/peeterj/scan-build/2012-12-12-4' because it contains no reports.
> 
> From the scan-build man page, it appears that this is how to use this utility, but doing so just results in make being called as is.  In what way is the makefile for the project supposed to be modified to use scan-build?
> 
> -- 
> Peeter
> _______________________________________________
> cfe-dev mailing list
> cfe-dev at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20121212/a37b88f5/attachment.html>