dSupport --dynamic-list-data

Fixes #1320

elf/cmdline.cc

@@ -93,6 +93,7 @@ inline const char helpmsg[] = R"(
   --execute-only              Make executable segments unreadable
   --dp                        Ignored
   --dynamic-list=FILE         Read a list of dynamic symbols (implies -Bsymbolic)
+  --dynamic-list-data         Add data symbols to dynamic symbols
   --eh-frame-hdr              Create .eh_frame_hdr section
     --no-eh-frame-hdr
   --exclude-libs LIB,LIB,..   Mark all symbols in given libraries as hidden
@@ -1304,6 +1305,8 @@ std::vector<std::string> parse_nonpositional_args(Context<E> &ctx) {
     } else if (read_arg("dynamic-list")) {
       ctx.arg.Bsymbolic = BSYMBOLIC_ALL;
       append(ctx.dynamic_list_patterns, parse_dynamic_list(ctx, arg));
+    } else if (read_arg("dynamic-list-data")) {
+      ctx.arg.dynamic_list_data = true;
     } else if (read_arg("export-dynamic-symbol")) {
       ctx.dynamic_list_patterns.push_back({arg, "<command line>"});
     } else if (read_arg("export-dynamic-symbol-list")) {

elf/mold.h

@@ -1799,6 +1799,7 @@ struct Context {
     bool detach = true;
     bool discard_all = false;
     bool discard_locals = false;
+    bool dynamic_list_data = false;
     bool eh_frame_hdr = true;
     bool emit_relocs = false;
     bool enable_new_dtags = true;

elf/passes.cc

@@ -1929,6 +1929,9 @@ static bool should_export(Context<E> &ctx, Symbol<E> &sym) {
 
   switch (sym.ver_idx) {
   case VER_NDX_UNSPECIFIED:
+    if (ctx.arg.dynamic_list_data)
+      if (u32 ty = sym.get_type(); ty != STT_FUNC && ty != STT_GNU_IFUNC)
+        return true;
     if (ctx.arg.shared)
       return !((ObjectFile<E> *)sym.file)->exclude_libs;
     return ctx.arg.export_dynamic;

test/elf/dynamic-list-data.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+. $(dirname $0)/common.inc
+
+cat <<EOF | $CC -o $t/a.o -c -xc -
+int foo = 5;
+void bar() {}
+int main() {}
+EOF
+
+$CC -B. -o $t/exe $t/a.o -Wl,-dynamic-list-data
+readelf -W --dyn-syms $t/exe > $t/log
+grep -wq foo $t/log
+! grep -wq bar $t/log || false