Boost::Accumulators: Shadow Variables and Unused Globals Cause Warnings/Errors When Headers Are Not in System Path

[gerickson@…]

I've recently added Boost to an Xcode 3.1.2 project with the following warnings enabled in GCC/G++ 4.0.1:

-Werror -Wreturn-type -Wunused-function -Wunused-label -Wunused-variable -Wshadow

Unfortunately, when boost is not installed in a "system" path--as is the case here--unused and shadow variable warnings cause the build to fail when warnings are treated as errors. This issue last came up for me about a year ago in 1_35_0 with filesystem.hpp:

​http://article.gmane.org/gmane.comp.lib.boost.user/38297/match=shadow+variables+cause

The included headers this time are:

boost/accumulators/accumulators.hpp boost/accumulators/statistics/stats.hpp boost/accumulators/statistics/rolling_mean.hpp

To test and fix, I isolated with:

printf "#include <${BoostHeader}>\nint main(void) { return 0; }" | /Developer/usr/bin/gcc-4.0 -x c++ -Wall -Wshadow -Werror -o test -I${BoostRoot}/boost/include -

The patch to address this is as follows and impacts the headers below:

boost/accumulators/framework/accumulator_set.hpp boost/accumulators/framework/accumulators/droppable_accumulator.hpp boost/accumulators/statistics/rolling_mean.hpp boost/accumulators/statistics/rolling_window.hpp boost/accumulators/statistics_fwd.hpp

Patches for other headers to be filed separately. Because this problem seems to come up frequently, perhaps there is a way -Wshadow and -Wall can be forced for all unit tests?

[gerickson@…]

Patch for Boost::Accumulators -Wshadow and -Wunused Errors

[Eric Niebler]

(In [55050]) eliminate shadow warnings and unused variable warnings, fixes #3262, fixed #3276, fixes #3031