Re: libgcc move to the top level

[Paolo Bonzini <paolo dot bonzini at lu dot unisi dot ch>]

> +.PHONY: check installcheck
> +check: check-subdir
> +installcheck: installcheck-subdir

Why the dependencies?

> +# If we have -fvisibility=hidden, then we need to generate hide
> +# lists for object files implemented in assembly.  The default
> +# pseudo-op for this is ".hidden", but can be overridden with
> +# ASM_HIDDEN_OP.
> +ifeq ($(ASM_HIDDEN_OP),)
> +ASM_HIDDEN_OP = .hidden
> +endif

This is a good candidate to be set in config.host (only Darwin
sets it, and it's already converted to toplevel libgcc) instead
of the Makefile.


> +# Test -fvisibility=hidden.  We need both a -fvisibility=hidden on
> +# the command line, and a #define to prevent libgcc2.h etc from
> +# overriding that with #pragmas.  The dance with @ is to prevent
> +# echo from seeing anything it might take for an option.
> +# echo turns the \$\$\$\$ into $$$$ and when make sees it it
> +# becomes $$ and the shell substitutes the pid. Makes for a
> +# slightly safer temp file.
> +vis_hide := $(strip $(subst @,-,\
> +    $(shell if echo 'void foo(void); void foo(void) {}' | \
> +          $(gcc_compile_bare) -fvisibility=hidden -Werror \
> +          -c -xc - -o vis_temp_file$$$$.o 2> /dev/null; \
> +          then echo @fvisibility=hidden @DHIDE_EXPORTS; \
> +          rm vis_temp_file$$$$.o 2> /dev/null; \
> +          fi)))

Consider moving this to configure.ac, after the config.host fragment. 
You can reuse some code in libffi's configure.ac, like this:

AC_CACHE_CHECK([for __attribute__((visibility("hidden")))],
    libgcc_cv_hidden_visibility_attribute, [
        echo 'int __attribute__ ((visibility ("hidden"))) foo (void) { 
return 1; }' > conftest.c
        libgcc_cv_hidden_visibility_attribute=no
        if AC_TRY_COMMAND(${CC-cc} -Werror -S conftest.c -o conftest.s 
1>&AS_MESSAGE_LOG_FD); then
            if grep "\\$ASM_HIDDEN_OP.*foo' conftest.s >/dev/null; then
                libgcc_cv_hidden_visibility_attribute=yes
            fi
        fi
        rm -f conftest.*
    ])

if test $libgcc_cv_hidden_visibility_attribute = yes; then
    vis_hide='-fvisibility=hidden -DHIDE_EXPORTS'
else
    vis_hide=
fi
AC_SUBST(vis_hide)


> +ifeq ($(LIB2_SIDITI_CONV_FUNCS),)
> +  lib2funcs += $(subst XX,si,$(swfloatfuncs))
> +  lib2funcs += $(subst XX,di,$(dwfloatfuncs))
> +endif
> ...
> +ifneq ($(LIB2_SIDITI_CONV_FUNCS),)
> +# Build libgcc2.c for each conversion function, with a specific
> +# L<func> definition and LIBGCC2_UNITS_PER_WORD setting.  The DImode
> +# functions are built with a wordsize of 4; the TImode functions are
> +# built with the same labels, but a wordsize of 8.
> +
> +sifuncs = $(subst XX,si,$(swfloatfuncs))
> +difuncs = $(subst XX,di,$(dwfloatfuncs))
> +tifuncs = $(subst XX,ti,$(dwfloatfuncs))

Please extract [sdt]ifuncs out of the if, and use a single 
ifeq/else/endif for both cases.


> +$(patsubst %,%.vis,$(LIB1ASMFUNCS)): %.vis: %_s.o
> +	$(gen-hide-list)

Replace .o with $(objext).



> +libgcc.a libgcov.a libunwind.a libgcc_eh.a:
> +	-rm -f $@
> +
> +	objects="$(objects)";	

No blank lines (i.e. no lines with the tab only).


> +all: $(HOST_EXTRA)
> +install: $(HOST_EXTRA_INSTALL)
> +

Just add the dependencies in the target fragment.

It's ok if you post only an incremental patch, rather than the whole 
stuff again.

Thanks!

Paolo