File 0001-COFF-Check-for-symbols-defined-in-discarded-section.patch of Package mingw64-binutils

From 2219ae0b0ebe14373850b000c2abaa31dab1d741 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Fri, 15 Mar 2019 22:19:01 +0800
Subject: [PATCH] COFF: Check for symbols defined in discarded section

For LTO, a symbol may defined in discarded section.  We should mark it
as undefined so that LTO plugin will make IR definition available.

	PR ld/24267
	* coffgen.c (_bfd_coff_section_already_linked): Skip discarded
	section.
	* cofflink.c (coff_link_add_symbols): Check for symbols defined
	in discarded section.
---
 bfd/ChangeLog  | 8 ++++++++
 bfd/coffgen.c  | 3 +++
 bfd/cofflink.c | 6 +++++-
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/bfd/coffgen.c b/bfd/coffgen.c
index 5db35c7ddf..ccf4b4302c 100644
--- a/bfd/coffgen.c
+++ b/bfd/coffgen.c
@@ -2652,6 +2652,9 @@ _bfd_coff_section_already_linked (bfd *abfd,
   struct bfd_section_already_linked_hash_entry *already_linked_list;
   struct coff_comdat_info *s_comdat;
 
+  if (sec->output_section == bfd_abs_section_ptr)
+    return FALSE;
+
   flags = sec->flags;
   if ((flags & SEC_LINK_ONCE) == 0)
     return FALSE;
diff --git a/bfd/cofflink.c b/bfd/cofflink.c
index e4031b9a31..ac07d05e57 100644
--- a/bfd/cofflink.c
+++ b/bfd/cofflink.c
@@ -310,7 +310,9 @@ coff_link_add_symbols (bfd *abfd,
 	    case COFF_SYMBOL_GLOBAL:
 	      flags = BSF_EXPORT | BSF_GLOBAL;
 	      section = coff_section_from_bfd_index (abfd, sym.n_scnum);
-	      if (! obj_pe (abfd))
+	      if (discarded_section (section))
+		section = bfd_und_section_ptr;
+	      else if (! obj_pe (abfd))
 		value -= section->vma;
 	      break;
 
@@ -327,6 +329,8 @@ coff_link_add_symbols (bfd *abfd,
 	    case COFF_SYMBOL_PE_SECTION:
 	      flags = BSF_SECTION_SYM | BSF_GLOBAL;
 	      section = coff_section_from_bfd_index (abfd, sym.n_scnum);
+	      if (discarded_section (section))
+		section = bfd_und_section_ptr;
 	      break;
 	    }
 
-- 
2.21.0