[glibc] Makerules: Generate shlib.lds with -fuse-ld=bfd

[glibc] Makerules: Generate shlib.lds with -fuse-ld=bfd

[Fangrui Song]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=2ae7990542e1955097aa21943e416dec70f867fa

commit 2ae7990542e1955097aa21943e416dec70f867fa
Author: Fangrui Song <maskray@google.com>
Date:   Tue Nov 8 20:56:59 2022 -0800

    Makerules: Generate shlib.lds with -fuse-ld=bfd
    
    lld does not dump a linker script with --verbose (it does not use a
    linker script driven design and lots of linker processing is not
    serializable as a linker script anyway).  With the default
    --with-default-link=no build, $@T is empty and makes `test -s $@T` fail.
    
    Just dump the linker script with -fuse-ld=bfd.  lld since 15
    (https://reviews.llvm.org/D124656) supports custom RELRO sections in the
    GNU ld dumped linker script.
    
    Reviewed-by: Sam James <sam@gentoo.org>

Diff:
---
 Makerules | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Makerules b/Makerules
index 09c0cf8357..a41491429e 100644
--- a/Makerules
+++ b/Makerules
@@ -546,14 +546,16 @@ endef
 
 ifeq (yes,$(use-default-link))
 # If the linker is good enough, we can let it use its default linker script.
+# In the long term the custom linker script will be removed.
 shlib-lds =
 shlib-lds-flags =
 else
 # binutils only position loadable notes into the first page for binaries,
 # not for shared objects
+# lld --verbose does not dump a linker script.  Use -fuse-ld=bfd.
 $(common-objpfx)shlib.lds: $(common-objpfx)config.make $(..)Makerules
 	$(LINK.o) -shared -Wl,-O1 \
-		  -nostdlib -nostartfiles \
+		  -nostdlib -nostartfiles -fuse-ld=bfd \
 		  $(sysdep-LDFLAGS) $(rtld-LDFLAGS) $(LDFLAGS.so) \
 		  -Wl,--verbose 2>/dev/null | \
 	  sed > $@T \