Package: g++-4.4 Version: 4.4.2-9 Severity: normal
A short example is the following, where none of the values of the two ++i subexpresions is used inside their enclosing expression, ... and in that sense we should get the error message twice ..., but the both values are used later, namely the first is used at the second, and the second is used in the body of the for loop. $ cat test02.cxx #include <iostream> int main( void ) { for ( int i=0 ; (++i)<99 , i<9 ; ++i ) { std::cout << i << std::endl; } return 0; } $ /usr/bin/g++ --version | head -1 g++ (Debian 4.4.2-9) 4.4.3 20100108 (prerelease) $ /usr/bin/g++ -Wall test02.cxx test02.cxx: In function 'int main()': test02.cxx:4: warning: value computed is not used $ ./a.out 1 3 5 7 $ If a subexpression is anonym having address not accessible by the other parts of the program, then it is probably true, that if that subexpression has no effect on the enclosing expression, then the value of that subexpression is not used at all. However, if the values of the subexpression is stored at a lefvalues accessible from other parts of the program, then we can not state, that the value computed is not used. Thanks for your voluntary efforts, Peter PROHLE. -- System Information: Debian Release: squeeze/sid APT prefers testing APT policy: (500, 'testing') Architecture: amd64 (x86_64) Kernel: Linux 2.6.32-trunk-amd64 (SMP w/4 CPU cores) Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968) Shell: /bin/sh linked to /bin/dash Versions of packages g++-4.4 depends on: ii gcc-4.4 4.4.2-9 The GNU C compiler ii gcc-4.4-base 4.4.2-9 The GNU Compiler Collection (base ii libc6 2.10.2-2 GNU C Library: Shared libraries ii libgmp3c2 2:4.3.2+dfsg-1 Multiprecision arithmetic library ii libmpfr1ldbl 2.4.2-3 multiple precision floating-point ii libstdc++6-4.4-dev 4.4.2-9 The GNU Standard C++ Library v3 (d g++-4.4 recommends no packages. Versions of packages g++-4.4 suggests: pn g++-4.4-multilib <none> (no description available) pn gcc-4.4-doc <none> (no description available) pn libstdc++6-4.4-dbg <none> (no description available) -- no debconf information -- To UNSUBSCRIBE, email to debian-gcc-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20100221194138.4750.20623.report...@pc-56.chello.hu