On Tue, Nov 20, 2018 at 08:47:14AM +0100, Landry Breuil wrote:
> On Mon, Nov 19, 2018 at 11:44:28PM -0500, George Koehler wrote:
> > On Mon, 19 Nov 2018 13:31:25 -0500
> > George Koehler <kern...@gmail.com> wrote:
> >
> > > My powerpc machine is using the gcc 6 diff from
> > > https://marc.info/?l=openbsd-ports&m=154165621429861&w=2
> > >
> > > This is using gcc-6.4.0p2 as ports-gcc, and has now failed to build
> > > devel/cmake.... (It fails) because gcc 6 warns when linking any
> > > C++ program:
> > >
> > > $ eg++ -o simple simple.cc
> > > /usr/local/lib/gcc/powerpc-unknown-openbsd6.4/6.4.0/../../../libestdc++.so.18.0:
> > > warning: sprintf() is often misused, please use snprintf()
> >
> > I now propose a patch for lang/gcc/6 that silences the above warning.
> > With this patch, lang/gcc/6 builds devel/cmake successfully. The
> > patch removes sprintf() from libestdc++.so but doesn't touch other
> > sprintf() calls in /usr/local/include/c++/6.4.0/ext/throw_allocator.h;
> > I did use base-gcc's /usr/include/g++/ext/throw_allocator.h as an
> > example of snprintf().
>
> Sadly, even if i personally would like those warning messages to go away
> as they never served any purpose in the ports land (and caused griefs
> from upstream in the past, and issues like this one..) i dont think this
> diff can be accepted. Iirc __builtin_xxx might do more things, and some
> developers have a strong opinion about keeping the warnings; so cmake
> might have to be adapted to ignore them ?
So, the warning comes from libestdc++, and we dont see it on amd64
because it uses lld (which doesnt trigger the warning), and not on i386
because it uses clang so libc++.
After discussing it with espie it might be better to use
__builtin_snprintf instead of just snprintf - with that the warning msg
should go away. That's what i'm testing in the current macppc bulk.
In the end i was wrong, and your analysis was right :)
Landry
$OpenBSD$
Silence this linker warning:
/usr/local/lib/gcc/powerpc-unknown-openbsd6.4/6.4.0/../../../libestdc++.so.18.0:
warning: sprintf() is often misused, please use snprintf()
Index: libstdc++-v3/src/c++11/debug.cc
--- libstdc++-v3/src/c++11/debug.cc.orig
+++ libstdc++-v3/src/c++11/debug.cc
@@ -660,7 +660,7 @@ namespace
else if (__builtin_strcmp(name, "address") == 0)
{
char buf[64];
- int ret = __builtin_sprintf(buf, "%p", inst._M_address);
+ int ret = __builtin_snprintf(buf, sizeof buf, "%p", inst._M_address);
print_word(ctx, buf, ret);
}
else
@@ -712,7 +712,7 @@ namespace
else if (__builtin_strcmp(name, "sequence") == 0)
{
assert(iterator._M_sequence);
- int written = __builtin_sprintf(buf, "%p", iterator._M_sequence);
+ int written = __builtin_snprintf(buf, sizeof buf, "%p",
iterator._M_sequence);
print_word(ctx, buf, written);
}
else if (__builtin_strcmp(name, "seq_type") == 0)
@@ -797,7 +797,7 @@ namespace
}
int written
- = __builtin_sprintf(buf, "@ 0x%p {\n", inst._M_address);
+ = __builtin_snprintf(buf, sizeof buf, "@ 0x%p {\n", inst._M_address);
print_word(ctx, buf, written);
if (inst._M_type)
@@ -853,7 +853,7 @@ namespace
}
int written
- = __builtin_sprintf(buf, "@ 0x%p\n", ite._M_sequence);
+ = __builtin_snprintf(buf, sizeof buf, "@ 0x%p\n",
ite._M_sequence);
print_word(ctx, buf, written);
}
@@ -951,8 +951,8 @@ namespace
if (param._M_kind == _Parameter::__integer)
{
int written
- = __builtin_sprintf(buf, "%ld",
- param._M_variant._M_integer._M_value);
+ = __builtin_snprintf(buf, sizeof buf, "%ld",
+ param._M_variant._M_integer._M_value);
print_word(ctx, buf, written);
}
else if (param._M_kind == _Parameter::__string)
@@ -1012,7 +1012,7 @@ namespace __gnu_debug
if (_M_line > 0)
{
char buf[64];
- int written = __builtin_sprintf(buf, "%u:", _M_line);
+ int written = __builtin_snprintf(buf, sizeof buf, "%u:", _M_line);
print_word(ctx, buf, written);
go_to_next_line = true;
}
