http://llvm.org/docs/LibFuzzer.html
I'm doing some works with libfuzzer now but when I do with the official toy example. when i run this command:
clang++ -fsanitize=address -fsanitize-coverage=edge test-fuzzer.cc Fuzzer*.o
there is an error happening that
clang: error: invalid value 'edge' in 'fsanitize-coverage=edge'
it seems that clang supports this argument but i'm wondering how i can see what value is supported...
i installed llvm 3.6 by apt-get with unbuntu14.04...
The syntax of the fsanitize-coverage= flag has been changed, as described in this commit message from May 2015. This bit is particularly relevant to you:
Original semantics of -fsanitize-coverage flag is preserved:
* -fsanitize-coverage=0 disables the coverage
* -fsanitize-coverage=1 is a synonym for -fsanitize-coverage=func
* -fsanitize-coverage=2 is a synonym for -fsanitize-coverage=bb
* -fsanitize-coverage=3 is a synonym for -fsanitize-coverage=edge
* -fsanitize-coverage=4 is a synonym for -fsanitize-coverage=edge,indirect-calls
So you might try -fsanitize-coverage=3.
Related
I am using coverity to analyze my code.
but when I configured cov, got an error.
> cov-configure --config
> /home/opt/coverity/Coverity/cov-admin/cov-conf/config/coverity_config_armcc.xml
> --comptype clang --compiler ****** --template
got an error:
Unknown compiler type clang
The only supported compiler types are:
******
So I'm doubt that if coverity supports clang compiler, or I have done something wrong.
The coverity version is 8.
BRs.
Coverity 8 definitely supports Clang. The issue is you're using --comptype clang - the comptype for Clang is --comptype clangcc (note the extra cc).
If you're in doubt, cov-configure --list-compiler-types is a good place to start, as is the documentation.
Note that so long as your Clang binary has the default name, cov-configure --clang should be all you need. Otherwise I strongly recommend you use --template on your cov-configure command line as well, as the CIT implementation for Clang makes heavy usage of "required" arguments and you're unlikely to get a successful capture of your build without using --template.
I have written and built an R package that depends on Rcpp and requires the C++0x standard (for using the tgamma function in C++). I have tested the package on various desktop computers and operating systems, and it always seems to install and work fine. However, I would also like to use the package on an HPC server. When I try to install the package there in my local R library tree using R CMD INSTALL test (where test is the name of the package), I get the following error message from the compiler:
/usr/include/c++/4.4.7/c++0x_warning.h(31): catastrophic error: #error directive: This file requires compiler and library support for the upcoming ISO C++ standard, C++0x. This support is currently experimental, and must be enabled with the -std=c++0x or -std=gnu++0x compiler options.
#error This file requires compiler and library support for the upcoming \
^
compilation aborted for Metropolis_Sampler_Beta_Edgewise_Cpp_Statistics.cpp (code 4)
make: *** [Metropolis_Sampler_Beta_Edgewise_Cpp_Statistics.o] Error 4
ERROR: compilation failed for package ‘test’
It basically tells me that I should enable C++0x support when the compiler is called (as in this post). Yet, I thought adding the statement CXX_STD = CXX11 to the src/Makevars file in the R package would actually tell the compiler that this version needs to be used. And indeed that seems to be the case on various desktop computers I have tried. So my question is: how can I tell the compiler on the server that this C++ version should be used for compilation? Alternatively, how else can I install the package?
On the server, I load the module for R by entering module load math/R on the terminal before trying to install the package, and it reports back that the following modules were loaded:
Loading module dependency 'compiler/intel/13.1'.
Loading module dependency 'numlib/mkl/11.0.5'.
Edit 1: The server is a German university cluster called bwUniCluster. It is based on KITE 2.0/RHEL6.5/Lustre 2.5.2. As far as I can tell from the module message reported above, it seems to be the Intel C++ Compiler XE (ICPC) version 13.1.3. But actually I have no clue about compilers, so if you need to know anything more specific, please let me know.
Edit 2 It's also possible to execute module load compiler/gnu/4.9 on the terminal before I try to install the package. This results in the following error message (similar as the one above), which leads me to think that this is not a version problem:
/pfs/data1/software_uc1/bwhpc/common/compiler/gnu/4.9.2/bin/../include/c++/4.9.2/bits/c++0x_warning.h(32): catastrophic error: #error directive: This file requires compiler and library support for the ISO C++ 2011 standard. This support is currently experimental, and must be enabled with the -std=c++11 or -std=gnu++11 compiler options.
#error This file requires compiler and library support for the \
^
compilation aborted for Metropolis_Sampler_Beta_Edgewise_Cpp_Statistics.cpp (code 4)
make: *** [Metropolis_Sampler_Beta_Edgewise_Cpp_Statistics.o] Error 4
ERROR: compilation failed for package ‘test’
Edit 3: One of the comments suggests that both the R package and R itself need to be compiled using the same compiler version. Is this correct? R was built using g++ 4.4.7 on this machine. Does this mean that the only feasible solution is to convince the sys admin to recompile R with the other 4.9.2 compiler and provide it as a new module? I find this hard to believe, given the following sentence in the "Writing R Extensions" manual:
On these platforms, it is necessary to select a different compiler for C++11, via personal or site Makevars files.
The solution was indeed to recompile R on the server with a newer compiler, in this case Intel 14 (as discussed in Edit 3 in the original post). The sys admin was so kind to set up a new module for this R version.
when I install Ns2.28 on ubuntun10.04(64 bit), there are some errors.
The first error is the version of gcc. The install file in the folder which is in ns2.28-allinone set the version of gcc as 3.4.I set the version the number of my gccc which is 4.4. so the error comes。 the error is
./classfier/classfier-hash.h:120 error: cast from void* to int loss pression
I know this error occur because of the type changed. I want to know whether the reason of this error is the version is modified by me. if yes,whether there are some patch filed to used.
I'm running Clang 3.4 on Ubuntu 12.10 (from http://llvm.org/apt/). I ran the analyzer (clang --analyze) over some code, and it found a couple of issues:
Blah.C:429:9: warning: Declared variable-length array (VLA) has zero size
unsigned char separatedData[groupDataLength];
^~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~
But the specific issue isn't important. I want to know the steps of how it came to that conclusion (the code is complex enough for me not to see it within 15 mins).
I see a screenshot from the Clang site that shows steps of working viewed in a web browser:
That's probably obtained from Xcode.
The question is: how do I get Clang to output such steps of working from the command line? Or even output results to a browser if it so wishes? This would make the analyzer significantly more useful, and make fixing things much quicker.
(I have noticed that GCC's documentation is very excellent, but Clang/LLVM's documentation is very poor. I've tried "clang --analyze -Xanalyzer '-v'" as a stab in the dark to tell the analyzer to be more verbose -- the -Xanalyzer switch was from the man pages.)
In addition to text output on the console:
clang++ --analyze -Xanalyzer -analyzer-output=text main.cpp
You can get the full html output:
clang++ --analyze -Xanalyzer -analyzer-output=html -o html-dir main.cpp
Additionally, you can select specific checkers to enable. This page lists available checks. For example, you can enable all of the C++ checks in the alpha group using the flags:
-Xanalyzer -analyzer-checker=alpha.cplusplus
http://coliru.stacked-crooked.com/a/7746c4004704d4a7
main.cpp:5:1: warning: Potential leak of memory pointed to by 'x'
}
^
main.cpp:4:12: note: Memory is allocated
int *x = new int;
^~~~~~~
main.cpp:5:1: note: Potential leak of memory pointed to by 'x'
}
^
Apparently the front end exposes
-analyzer-config <Option Name>=<Value>
E.g.
-analyzer-config -analyzer-checker=alpha.cplusplus
which might be better supported than -Xanalyzer and may be getting extended to support options to individual checkers: http://lists.cs.uiuc.edu/pipermail/cfe-dev/2014-October/039552.html
You are on the right track, but to get the full trace leading to a bug you additionally need to ask clang for output in text format (don't ask why). Since you will probably need to adjust e.g. include paths or defines for your project anyway I'd suggest you use clang-check which acts as a wrapper around clang's analyzer pass. It can also hook into the static analyzer tools exposed in e.g. scan-build. You can then
$ clang-check -analyze -extra-arg -Xclang -extra-arg -analyzer-output=text
Like you wrote the documentation for these very nice tools is abysmal. I cobbled above call together from bits and pieces from Chandler Carruth's GoingNative2013 talk.
You have to use scanbuild: http://clang-analyzer.llvm.org/scan-build.html
You type the commands that generate your build, but you pre-pend them with scan-build.
Example:
instead of
make
type
scan-build make
instead of
./configure
make
type
scan-build ./configure
scan-build make
Clear the build before launching the analyzer, otherwise make will state that everything has been built already and the analyzer will not run.
I need to install Rstan for a data analysis class. The instructions are posted here http://code.google.com/p/stan/wiki/RStanGettingStarted. I'm running Mac OS 10.5.8 and R 2.15.1 GUI 1.52 Leopard build 32-bit (6188). I just installed Xcode version 3.1.4, the Xcode c++ compiler that is compatible with leopard (I had to get a mac developer account to do this).
Per the Stan installation instruction, I entered the following code to see if my compiler was working:
library(inline)
library(Rcpp)
src <- '
std::vector<std::string> s;
s.push_back("hello");
s.push_back("world");
return Rcpp::wrap(s);
'
hellofun <- cxxfunction(body = src, includes = '', plugin = 'Rcpp', verbose = FALSE)
cat(hellofun(), '\n')
It returns the following error:
Error in compileCode(f, code, language = language, verbose = verbose) :
Compilation ERROR, function(s)/method(s) not created!
Library/Frameworks/R.framework/Versions/2.15/Resources/library/
Rcpp/include/Rcpp/internal/export.h: In function ‘void
Rcpp::internal::export_range__dispatch(SEXPREC*, InputIterator,
Rcpp::traits::r_type_primitive_tag)’:
/Library/Frameworks/R.framework/Versions/2.15/Resources/
library/Rcpp/include/Rcpp/internal/export.h:56: internal
compiler error: Bus error
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://developer.apple.com/bugreporter> for
instructions.
make: *** [file795214e66510.o] Error 1
In addition: Warning message:
running command '/Library/Frameworks/R.framework/Resources/bin/
R CMD SHLIB file795214e66510.cpp 2>
file795214e66510.cpp.err.txt' had status 1
When I try to install stan:
install.packages('rstan', type = 'source') ]
I get this warning:
Warning message:
In install.packages("rstan", type = "source") :
installation of package ‘rstan’ had non-zero exit status
I have no idea how C++ works. All of my coding experience is in R and has not before required compiling into C++. I've been trying really hard to figure out what's wrong for the last 4 hours or so, googling these error messages over and over without much luck. Any help would be greatly appreciated and would also help about 10 other students in my class who are having identical or analogous problems. Thank you very, very much.
This looks to me like an issue with the installation of your C++ compiler or with your installation of the Rcpp package, rather than an issue with the rstan package. However, if g++ is causing an intractable problem for you, an alternative is the clang compiler, which should work with Rcpp and rstan if you create $HOME/.R/Makevars with these two lines
CC=clang
CXX=clang++
As mentioned in another answer, the first step is to get Rcpp working on your Mac (i.e,. at least pass the hello world example).
A similar issue for Rcpp previously:
https://stat.ethz.ch/pipermail/r-sig-mac/2010-July/007574.html
In addition, from this webpage http://useyourloaf.com/blog/2011/03/21/compiler-options-in-xcode-gcc-or-llvm.html, it seems that gcc 4.2 and 4.0 are both in Xcode 3.14 (not sure as it does not say it's 3.14). So try to make sure gcc 4.2.1 is used by R is important. Executing the following in a terminal will show what is the current version of gcc.
$ g++ -v