[Boost-bugs] [Boost C++ Libraries] #9239: Implicit type conversion without warning, although Wconversion used

Subject: [Boost-bugs] [Boost C++ Libraries] #9239: Implicit type conversion without warning, although Wconversion used
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-10-11 15:49:45

#9239: Implicit type conversion without warning, although Wconversion used
-----------------------------------------+-----------------------------
 Reporter:  Daniel Rings <topwohnung@…>  |      Owner:  matthiasschabel
     Type:  Bugs                         |     Status:  new
Milestone:  To Be Determined             |  Component:  units
  Version:  Boost 1.54.0                 |   Severity:  Problem
 Keywords:  units auto                   |
-----------------------------------------+-----------------------------
 When defining a variable with automatic type recognition,
 {{{
 auto inv_time = 1/si::second;
 }}}
 this instruction
 {{{
 inv_time = 0.4/si::second;
 }}}
 does not generate a warning (using -Wconversion), while
 {{{
 auto p = 3;
 p = 1.0/2.0;
 }}}
 generates a warning, as it should. Is there any reason for the different
 behavior in both cases?
 It should be mentioned that this is not contingent to "auto", for
 {{{
 quantity<si::time,int>  time = 1/(1/si::second);
 time = 0.4*si::second;
 }}}
 compiles without warning, too (and time = 0 s in the end). I thought
 implicit typecasts with possible loss of precision were forbidden or would
 at least trigger a warning.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9239>
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