From ccd27807aa87c739fcbb053b191a241eaa2c1e34 Mon Sep 17 00:00:00 2001
From: Rui Ueyama <ruiu@cs.stanford.edu>
Date: Mon, 10 May 2021 14:05:21 +0900
Subject: [PATCH] Do not add unreferenced DSO symbols to .dynsym

---
 passes.cc       |  6 ++----
 test/dt_init.sh | 16 ++++++++--------
 test/shared.sh  |  7 +++++--
 3 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/passes.cc b/passes.cc
index 7b84b8ae..00b11e39 100644
--- a/passes.cc
+++ b/passes.cc
@@ -417,11 +417,9 @@ void scan_rels(Context<E> &ctx) {
 
   tbb::parallel_for((i64)0, (i64)files.size(), [&](i64 i) {
     for (Symbol<E> *sym : files[i]->symbols) {
-      if (sym->file != files[i])
-        continue;
-      if (sym->is_imported || sym->is_exported)
+      if (!files[i]->is_dso && (sym->is_imported || sym->is_exported))
         sym->flags |= NEEDS_DYNSYM;
-      if (sym->flags)
+      if (sym->file == files[i] && sym->flags)
         vec[i].push_back(sym);
     }
   });
diff --git a/test/dt_init.sh b/test/dt_init.sh
index 0a2c7f06..89dfff4c 100755
--- a/test/dt_init.sh
+++ b/test/dt_init.sh
@@ -18,17 +18,17 @@ EOF
 clang -fuse-ld=`pwd`/../mold -o $t/exe $t/a.o
 readelf -a $t/exe > $t/log
 
-grep -Pq '\(INIT\)\s+0x233010' $t/log
-grep -Pq '\(FINI\)\s+0x233000' $t/log
-grep -Pq '0000000000233010\s+0 FUNC    GLOBAL HIDDEN    \d+ _init$' $t/log
-grep -Pq '0000000000233000\s+0 FUNC    GLOBAL HIDDEN    \d+ _fini$' $t/log
+grep -Pq '\(INIT\)\s+0x201010' $t/log
+grep -Pq '\(FINI\)\s+0x201000' $t/log
+grep -Pq '0000000000201010\s+0 FUNC    GLOBAL HIDDEN    \d+ _init$' $t/log
+grep -Pq '0000000000201000\s+0 FUNC    GLOBAL HIDDEN    \d+ _fini$' $t/log
 
 clang -fuse-ld=`pwd`/../mold -o $t/exe $t/a.o -Wl,-init,init -Wl,-fini,fini
 readelf -a $t/exe > $t/log
 
-grep -Pq '\(INIT\)\s+0x233119' $t/log
-grep -Pq '\(FINI\)\s+0x23311a' $t/log
-grep -Pq '0000000000233119\s+0 NOTYPE  GLOBAL DEFAULT   \d+ init$' $t/log
-grep -Pq '000000000023311a\s+0 NOTYPE  GLOBAL DEFAULT   \d+ fini$' $t/log
+grep -Pq '\(INIT\)\s+0x201119' $t/log
+grep -Pq '\(FINI\)\s+0x20111a' $t/log
+grep -Pq '0000000000201119\s+0 NOTYPE  GLOBAL DEFAULT   \d+ init$' $t/log
+grep -Pq '000000000020111a\s+0 NOTYPE  GLOBAL DEFAULT   \d+ fini$' $t/log
 
 echo OK
diff --git a/test/shared.sh b/test/shared.sh
index 7ab83b27..b0fda6f9 100755
--- a/test/shared.sh
+++ b/test/shared.sh
@@ -6,10 +6,12 @@ t=$(pwd)/tmp/$(basename -s .sh $0)
 mkdir -p $t
 
 cat <<EOF | clang -fPIC -c -o $t/a.o -x assembler -
-.globl fn1, fn2
+.globl fn1, fn2, fn3
 fn1:
   call fn2@PLT
   ret
+fn3:
+  nop
 EOF
 
 clang -shared -fuse-ld=`pwd`/../mold -o $t/b.so $t/a.o
@@ -17,7 +19,7 @@ clang -shared -fuse-ld=`pwd`/../mold -o $t/b.so $t/a.o
 readelf --dyn-syms $t/b.so > $t/log
 
 grep -q '0000000000000000     0 NOTYPE  GLOBAL DEFAULT  UND fn2' $t/log
-grep -q '000000000003311c     0 NOTYPE  GLOBAL DEFAULT   15 fn1' $t/log
+grep -q '000000000000111c     0 NOTYPE  GLOBAL DEFAULT   15 fn1' $t/log
 
 cat <<EOF | clang -fPIC -c -o $t/c.o -xc -
 #include <stdio.h>
@@ -36,5 +38,6 @@ EOF
 
 clang -fuse-ld=`pwd`/../mold -o $t/exe $t/c.o $t/b.so
 $t/exe | grep -q hello
+! readelf --symbols $t/exe | grep -q fn3 || false
 
 echo OK