http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54140
Bug #: 54140
Summary: -Wswitch shouldn't complain about out-of-range values
that are cast to the correct type
Classification: Unclassified
Product: gcc
Version: 4.6.3
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: a...@aryeh.name
Version:
<<<
$ g++ -v
Using built-in specs.
COLLECT_GCC=/usr/bin/g++-4.6.real
COLLECT_LTO_WRAPPER=/usr/lib/gcc/i686-linux-gnu/4.6/lto-wrapper
Target: i686-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
4.6.3-1ubuntu5' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr
--program-suffix=-4.6 --enable-shared --enable-linker-build-id
--with-system-zlib --libexecdir=/usr/lib --without-included-gettext
--enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.6
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object
--enable-plugin --enable-objc-gc --enable-targets=all --disable-werror
--with-arch-32=i686 --with-tune=generic --enable-checking=release
--build=i686-linux-gnu --host=i686-linux-gnu --target=i686-linux-gnu
Thread model: posix
gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)
>>>
test.cpp:
<<<
enum Enum { A };
int main() {
Enum x = (Enum)72;
switch (x) {
case A: return 1;
case (Enum)72: return 0;
}
return 1;
}
>>>
Command line and output:
<<<
$ g++ -Wall -Wextra -Werror test.cpp -otest
test.cpp: In function ‘int main()’:
test.cpp:7:3: error: case value ‘72’ not in enumerated type ‘Enum’
[-Werror=switch]
cc1plus: all warnings being treated as errors
>>>
This would have been appropriate if I wrote "case 72:", but I didn't -- I wrote
"case (Enum)72:". This is an explicit indication that I want gcc to treat 72
as a member of Enum here, so I would expect no warning.
