Detect EAF flags in ipa-modref

[Jan Hubicka]

> Hi Jan,
> 
> >> This breaks bootstrap with go.
> >> 
> >> ../../gcc/go/gofrontend/go-diagnostics.cc: In function 'std::string expand_message(const char*, va_list)':
> >> ../../gcc/go/gofrontend/go-diagnostics.cc:110:61: error: '<anonymous>' may be used uninitialized [-Werror=maybe-uninitialized]
> >>   110 |                      "memory allocation failed in vasprintf");
> >>       |                                                             ^
> >
> > Well, this may be simply a false positive (except that the warning is
> > clearly mislocalted and cryptic) I was bootstrapping with go just few
> > minutes ago, so I wonder what configure flags you use?
> 
> I'm seeing the same on both i386-pc-solaris2.11 and
> sparc-sun-solaris2.11, so I don't think there are special configure
> flags involved.

When I configure with ../configure --enable-languages=go my build
eventually finishes fine on curren trunk:

/aux/hubicka/trunk-git/build-go/./gcc/gccgo -B/aux/hubicka/trunk-git/build-go/./gcc/ -B/usr/local/x86_64-pc-linux-gnu/bin/ -B/usr/local/x86_64-pc-linux-gnu/lib/ -isystem /usr/local/x86_64-pc-linux-gnu/include -isystem /usr/local/x86_64-pc-linux-gnu/sys-include   -g -O2 -I ../x86_64-pc-linux-gnu/libgo -static-libstdc++ -static-libgcc  -L ../x86_64-pc-linux-gnu/libgo -L ../x86_64-pc-linux-gnu/libgo/.libs -o cgo ../../gotools/../libgo/go/cmd/cgo/ast.go ../../gotools/../libgo/go/cmd/cgo/doc.go ../../gotools/../libgo/go/cmd/cgo/gcc.go ../../gotools/../libgo/go/cmd/cgo/godefs.go ../../gotools/../libgo/go/cmd/cgo/main.go ../../gotools/../libgo/go/cmd/cgo/out.go ../../gotools/../libgo/go/cmd/cgo/util.go zdefaultcc.go ../x86_64-pc-linux-gnu/libgo/libgotool.a
make[2]: Leaving directory '/aux/hubicka/trunk-git/build-go/gotools'
make[1]: Leaving directory '/aux/hubicka/trunk-git/build-go'

On Debian SLES machines.  Having preprocessed go-diagnostics.cc and
.uninit1 dump would probably help.

These are often false positives, but I saw similar warnings caused by
wrong EAF_UNUSED flag discovery which led to init code being optimized
out before inlining, so I would like to look into the dumps and figure
out if that is uninit acting funny or there is some real problem.

Honza
> 
> 	Rainer
> 
> -- 
> -----------------------------------------------------------------------------
> Rainer Orth, Center for Biotechnology, Bielefeld University