What preprocessor symbols does Coverity define for a build using 'cov-build'?

问题

We use Coverity's Scan Build service for free and open source projects. I am working through two Coverity findings on tainted parameters (TAINTED_SCALAR). The taint is a false positive, so I am trying to instrument the code with Coverity's __coverity_tainted_data_sanitize__ to clear the issue.

I want to guard the code that needs to use __coverity_tainted_data_sanitize__ because the function is only used with analysis builds using Coverity's cov-build tool. That is, I want to do something like:

void Foo(std::istream& is, ...)
{
    std::string name;
    is >> name;

#if <SOME_COVERITY_PREPROCESSOR_MACRO>
    __coverity_tainted_data_sanitize__(name);
#endif

    ...
}

Coverity has a couple of examples on using __coverity_tainted_data_sanitize__, but they don't show how to guard it. See for example, Function model example for Tainted Scalar and Explicitly document parameter passing mechanisms. I also could not find it when asking the preprocessor (see below).

What preprocessor macros does Coverity define to determine an analysis build?

Preprocessor Output

$ cov-build --dir ~/temp cpp -x c++ -dM </dev/null 2>&1 | egrep -i "(cov|anal)"
Coverity Build Capture (64-bit) version 7.7.0.4 on Linux 3.13.0-68-generic x86_64

Environmental Variables

I did find some environmental variables, but I prefer to avoid mapping environmental variables to preprocessor defines.

$ cov-build --dir ~/temp printenv 2>&1 | egrep -i "(cov|anal)"
Coverity Build Capture (64-bit) version 7.7.0.4 on Linux 3.13.0-68-generic x86_64
LD_LIBRARY_PATH=/home/cov-analysis/jars
LD_PRELOAD=/home/cov-analysis/bin/libcapture-linux64-${PLATFORM}.so
COVERITY_TEMP=/tmp/cov-98db841699284e11e33be37fe7061776
COVERITY_LD_LIBRARY_PATH=/home/cov-analysis/jars
COVERITY_JAVA14_WARNING_FILE=/home/temp/warn_about_java14_compilations
COVERITY_ENABLE_CEJ_PER_CLASS_ERROR_RECOVERY=1
COVERITY_IS_COMPILER_DESCENDANT=0
COVERITY_CONFIG_FILE=/home/cov-analysis/config/coverity_config.xml
COVERITY_COMMON_TEMP=/tmp
COVERITY_JAVA_CONFIG=javac#TEMPLATE##java#TEMPLATE##apt#TEMPLATE##javaw#TEMPLATE###
COVERITY_PREV_XML_CATALOG_FILES=
COVERITY_OUTPUT_ENCODING=UTF-8
COVERITY_COMPILER_PATH_MISMATCH_FILE=/home/temp/has_path_mismatches
COVERITY_ENABLE_CECS_WATCHDOG=1
COVERITY_PATHLESS_CONFIGS_FILE=/home/temp/has_pathless_configs
COVERITY_LD_PRELOAD=/home/cov-analysis/bin/libcapture-linux64-${PLATFORM}.so
COVERITY_BUILD_INVOCATION_ID=1
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/home/cov-analysis/bin
COVERITY_BIN=/home/cov-analysis/bin
COVERITY_IDIR=/home/temp
COVERITY_TOP_PROCESS=0
COVERITY_OUTPUT=/home/temp/build-log.txt
COVERITY_EMIT=/home/temp/emit
PWD=/home/cov-analysis
COVERITY_SITE_CC=VBCSCompiler;apt;c++;cc;cl;clang;clang++;csc;csc2;devenv;g++;g++-4.8;g++-4.9;g++-5.1.0;gcc;gcc-4.8;gcc-4.9;gcc-5.1.0;java;javac;javaw;ld;msbuild;xgcc
COVERITY_LOG=/home/temp/build-log.txt
COVERITY_SYSTEM_ENCODING=UTF-8
COVERITY_TOP_CONFIG=/tmp/cov-98db841699284e11e33be37fe7061776/cov-configure/coverity_config.xml
COVERITY_IS_COMPILER=0

Just in case its discussed... the library does read what appears to be a tainted value. However, its a datafile used for self tests, its located in /usr/share, and its not arbitrary user input. The library does not expose this particular functions to users, so I dont believe it can be abused in unexpected ways.

回答1:

Both cov-emit and cov-internal-emit-clang predefine the __COVERITY__ macro, which is probably what you want.

That said, I think you should be able to mark the defect as a false positive in the Coverity Scan web UI, and it won't show up anymore.

$ cov-build --dir ~/temp cpp -x c++ -dM &1 | egrep -i "(cov|anal)" Coverity Build Capture (64-bit) version 7.7.0.4 on Linux 3.13.0-68-generic x86_64

As an aside, this is looking at the macros predefined by cpp, not cov-translate. As far as I know, there is currently no straightforward way to dump all the macros predefined by cov-build/cov-translate.

来源：https://stackoverflow.com/questions/33719379/what-preprocessor-symbols-does-coverity-define-for-a-build-using-cov-build

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c++

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