[Boost-bugs] [Boost C++ Libraries] #9014: Warnings when compiling api_test_helpers.hpp

Subject: [Boost-bugs] [Boost C++ Libraries] #9014: Warnings when compiling api_test_helpers.hpp
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-08-19 10:52:39

#9014: Warnings when compiling api_test_helpers.hpp
----------------------------------+--------------------------
 Reporter:  gjasny@…              |      Owner:  timblechmann
     Type:  Bugs                  |     Status:  new
Milestone:  To Be Determined      |  Component:  atomic
  Version:  Boost Release Branch  |   Severity:  Cosmetic
 Keywords:                        |
----------------------------------+--------------------------
 Hello,

 clang 3.3 warns about about the truncation of the larger constant:

 {{{
 clang-linux.compile.c++.without-pth
 ../../../bin.v2/libs/atomic/test/native_api.test/clang-linux-3.3/debug
 /threading-multi/native_api.o
 In file included from native_api.cpp:12:
 ./api_test_helpers.hpp:268:35: warning: implicit conversion from 'int' to
 'unsigned char' changes value from 32640 to 128 [-Wconstant-conversion]
     test_additive_wrap<T>(((T)-1) << (sizeof(T) * 8 - 1));
     ~~~~~~~~~~~~~~~~~~    ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
 native_api.cpp:20:5: note: in instantiation of function template
 specialization 'test_integral_api<unsigned char>' requested here
     test_integral_api<unsigned char>();
     ^
 In file included from native_api.cpp:12:
 ./api_test_helpers.hpp:269:27: warning: implicit conversion from 'int' to
 'unsigned char' changes value from -32641 to 127 [-Wconstant-conversion]
     test_additive_wrap<T>(~ (((T)-1) << (sizeof(T) * 8 - 1)));
     ~~~~~~~~~~~~~~~~~~    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 ./api_test_helpers.hpp:268:35: warning: implicit conversion from 'int' to
 'unsigned short' changes value from 2147450880 to 32768 [-Wconstant-
 conversion]
     test_additive_wrap<T>(((T)-1) << (sizeof(T) * 8 - 1));
     ~~~~~~~~~~~~~~~~~~    ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
 native_api.cpp:24:5: note: in instantiation of function template
 specialization 'test_integral_api<unsigned short>' requested here
     test_integral_api<unsigned short>();
     ^
 In file included from native_api.cpp:12:
 ./api_test_helpers.hpp:269:27: warning: implicit conversion from 'int' to
 'unsigned short' changes value from -2147450881 to 32767 [-Wconstant-
 conversion]
     test_additive_wrap<T>(~ (((T)-1) << (sizeof(T) * 8 - 1)));
     ~~~~~~~~~~~~~~~~~~    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 4 warnings generated.
 }}}

 Thanks,
 Gregor

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9014>
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