http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46170
Summary: g++ wrongly rejects pointer-to-member in template
arguments
Product: gcc
Version: 4.4.4
Status: UNCONFIRMED
Severity: major
Priority: P3
Component: c++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: f...@csl.cornell.edu
The following reduced test case is wrongly rejected by g++-4.4 and g++-4.5:
============ test case: reduce.ii =================
namespace util {
struct option_value {
};
template <class T> struct options_map_impl {
typedef T options_struct_type;
typedef bool (*opt_func)(const option_value&, options_struct_type&);
template <class V, V K> static bool set_member_constant(const option_value&,
options_struct_type&, V options_struct_type::*);
template <class V, V options_struct_type::*mem, V K> static bool
set_member_constant(const option_value& opt, options_struct_type& t) {
return set_member_constant<V,K>(opt, t, mem);
}
};
}
struct cflat_options {
bool show_precharges;
};
typedef util::options_map_impl<cflat_options> options_map_impl_type;
class register_options_modifier {
typedef options_map_impl_type::opt_func modifier_type;
public: register_options_modifier();
register_options_modifier(const char* Mode, const modifier_type COM,
const char* h);
};
static const register_options_modifier
cflat_opt_mod_show_precharges("precharges",
&options_map_impl_type::set_member_constant<bool,
&cflat_options::show_precharges, true>, "show precharge expressions"),
cflat_opt_mod_no_show_precharges("no-" "precharges",
&options_map_impl_type::set_member_constant<bool,
&cflat_options::show_precharges, false>, "hide precharge expressions");
=========== end test case ===============
delta-reduced using:
#!/bin/sh -e
# reduce.sh
CXXFLAGS="-ansi -Woverloaded-virtual -W -Wextra -Wall -Wundef -Wshadow
-Wno-unused-parameter -Wpointer-arith -Wcast-qual -Wcast-align -Wconversion
-Werror -Wno-conversion -Wno-long-long"
# must pass g++-4.2 first
g++ $CXXFLAGS -c -o reduce.o reduce.ii
g++-4 -pipe -g -O2 $CXXFLAGS -x c++ reduce.ii -o reduce.o 2> reduce.err || :
grep -q "not a valid template argument" reduce.err
# exactly 4 lines of errors
el=`wc -l reduce.err | awk '{print $1;}'`
test $el -eq 4
============================================
diagnostic:
reduce.ii: In static member function 'static bool
util::options_map_impl<T>::set_member_constant(const util::option_value&, T&)
[with V = bool, V T::* mem = &cflat_options::show_precharges, V K = true, T =
cflat_options]':
reduce.ii:22: instantiated from here
reduce.ii:9: error: 'true' is not a valid template argument for type 'bool
cflat_options::*'
reduce.ii:9: error: it must be a pointer-to-member of the form `&X::Y'
============================================
it pass g++-4.2 and fails g++-4.4, g++-4.5:
f...@fangbook 163> g++ -v
Using built-in specs.
Target: i686-apple-darwin10
Configured with: /var/tmp/gcc/gcc-5664~105/src/configure --disable-checking
--enable-werror --prefix=/usr --mandir=/share/man
--enable-languages=c,objc,c++,obj-c++
--program-transform-name=/^[cg][^.-]*$/s/$/-4.2/ --with-slibdir=/usr/lib
--build=i686-apple-darwin10 --program-prefix=i686-apple-darwin10-
--host=x86_64-apple-darwin10 --target=i686-apple-darwin10
--with-gxx-include-dir=/include/c++/4.2.1
Thread model: posix
gcc version 4.2.1 (Apple Inc. build 5664)
f...@fangbook 164> g++-4 -v
Using built-in specs.
Target: i386-apple-darwin10.4.0
Configured with: ../gcc-4.4.4/configure --prefix=/sw --prefix=/sw/lib/gcc4.4
--mandir=/sw/share/man --infodir=/sw/lib/gcc4.4/info
--enable-languages=c,c++,fortran,objc,obj-c++,java --with-gmp=/sw
--with-libiconv-prefix=/sw --with-ppl=/sw --with-cloog=/sw --with-mpc=/sw
--with-system-zlib --x-includes=/usr/X11R6/include --x-libraries=/usr/X11R6/lib
--program-suffix=-fsf-4.4
Thread model: posix
gcc version 4.4.4 (GCC)
(for 4.5)
g++-4 -v
Using built-in specs.
COLLECT_GCC=g++-4
COLLECT_LTO_WRAPPER=/Volumes/MacSpare/sw/lib/gcc4.5/bin/../libexec/gcc/i386-apple-darwin10.4.0/4.5.0/lto-wrapper
Target: i386-apple-darwin10.4.0
Configured with: ../gcc-4.5.0/configure --prefix=/sw --prefix=/sw/lib/gcc4.5
--mandir=/sw/share/man --infodir=/sw/lib/gcc4.5/info
--enable-languages=c,c++,fortran,objc,obj-c++,java --with-gmp=/sw
--with-libiconv-prefix=/sw --with-ppl=/sw --with-cloog=/sw --with-mpc=/sw
--with-system-zlib --x-includes=/usr/X11R6/include --x-libraries=/usr/X11R6/lib
--program-suffix=-fsf-4.5
Thread model: posix
gcc version 4.5.0 (GCC)
===================================
keywords: rejects-valid, diagnostic
known-to-work: 4.2.1
known-to-fail: 4.4.4 4.5.0
This also used to work on 4.4.2, so it might be a branch regression.
