[binutils-gdb/binutils-2_37-branch] PR28106, build of 2.37 fails on FreeBSD and Clang

[Alan Modra]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=10b4dbbf281397e2827820c715c39559c7f7a29d

commit 10b4dbbf281397e2827820c715c39559c7f7a29d
Author: Alan Modra <amodra@gmail.com>
Date:   Tue Jul 20 18:46:57 2021 +0930

    PR28106, build of 2.37 fails on FreeBSD and Clang
    
    https://en.cppreference.com/w/cpp/types/NULL says NULL might be
    defined as nullptr.
    https://en.cppreference.com/w/cpp/language/reinterpret_cast says
    reinterpret_cast can't be used on nullptr.
    
            PR gold/28106
            PR gold/27815
            * gc.h (gc_process_relocs): Use static_cast in Section_id constructor.
    
    (cherry picked from commit b97bd976233ee4d43c2fe18f6356e62779cbe82d)

Diff:
---
 gold/ChangeLog | 6 ++++++
 gold/gc.h      | 4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/gold/ChangeLog b/gold/ChangeLog
index 79207900dfc..deb0aa504b5 100644
--- a/gold/ChangeLog
+++ b/gold/ChangeLog
@@ -1,3 +1,9 @@
+2021-07-20  Alan Modra  <amodra@gmail.com>
+
+	PR gold/28106
+	PR gold/27815
+	* gc.h (gc_process_relocs): Use static_cast in Section_id constructor.
+
 2021-07-18  Nick Clifton  <nickc@redhat.com>
 
 	* 2.37 release.
diff --git a/gold/gc.h b/gold/gc.h
index 6ebd81f3fd0..4a1368f5abe 100644
--- a/gold/gc.h
+++ b/gold/gc.h
@@ -247,7 +247,7 @@ gc_process_relocs(
 	      if (is_ordinary) 
 		(*secvec).push_back(Section_id(src_obj, dst_indx));
 	      else
-		(*secvec).push_back(Section_id(reinterpret_cast<Relobj*>(NULL), 0));
+		(*secvec).push_back(Section_id(static_cast<Relobj*>(NULL), 0));
               // If the target of the relocation is an STT_SECTION symbol,
               // make a note of that by storing -1 in the symbol vector.
               if (lsym.get_st_type() == elfcpp::STT_SECTION)
@@ -329,7 +329,7 @@ gc_process_relocs(
               if (is_ordinary && dst_obj != NULL)
 		(*secvec).push_back(Section_id(dst_obj, dst_indx));
 	      else
-		(*secvec).push_back(Section_id(reinterpret_cast<Relobj*>(NULL), 0));
+		(*secvec).push_back(Section_id(static_cast<Relobj*>(NULL), 0));
               (*symvec).push_back(gsym);
 	      (*addendvec).push_back(std::make_pair(
 					static_cast<long long>(symvalue),