diff --git a/elf/input-files.cc b/elf/input-files.cc
index 4fd9fdb5c3..4d1a0aee21 100644
--- a/elf/input-files.cc
+++ b/elf/input-files.cc
@@ -1224,7 +1224,6 @@ void SharedFile<E>::parse(Context<E> &ctx) {
 
   this->symbol_strtab = this->get_string(ctx, symtab_sec->sh_link);
   soname = get_soname(ctx);
-  dt_needed = read_dt_needed(ctx);
   version_strings = read_verdef(ctx);
 
   // Read a symbol table.
@@ -1267,16 +1266,13 @@ void SharedFile<E>::parse(Context<E> &ctx) {
 }
 
 template <typename E>
-std::vector<std::string_view> SharedFile<E>::read_dt_needed(Context<E> &ctx) {
-  // Get the contents of a .dynamic seciton
+std::vector<std::string_view> SharedFile<E>::get_dt_needed(Context<E> &ctx) {
+  // Get the contents of the dynamic segment
   std::span<Word<E>> dynamic;
-  for (ElfPhdr<E> &phdr : this->get_phdrs()) {
-    if (phdr.p_type == PT_DYNAMIC) {
+  for (ElfPhdr<E> &phdr : this->get_phdrs())
+    if (phdr.p_type == PT_DYNAMIC)
       dynamic = {(Word<E> *)(this->mf->data + phdr.p_offset),
                  phdr.p_memsz / sizeof(Word<E>)};
-      break;
-    }
-  }
 
   // Find a string table
   char *strtab = nullptr;
diff --git a/elf/mold.h b/elf/mold.h
index 36a40b7483..6556424183 100644
--- a/elf/mold.h
+++ b/elf/mold.h
@@ -1301,6 +1301,7 @@ class SharedFile : public InputFile<E> {
   void resolve_symbols(Context<E> &ctx) override;
   std::span<Symbol<E> *> get_symbols_at(Symbol<E> *sym);
   i64 get_alignment(Symbol<E> *sym);
+  std::vector<std::string_view> get_dt_needed(Context<E> &ctx);
   bool is_readonly(Symbol<E> *sym);
 
   void mark_live_objects(Context<E> &ctx,
@@ -1311,7 +1312,6 @@ class SharedFile : public InputFile<E> {
 
   std::string soname;
   std::vector<std::string_view> version_strings;
-  std::vector<std::string_view> dt_needed;
   std::vector<ElfSym<E>> elf_syms2;
 
 private:
diff --git a/elf/passes.cc b/elf/passes.cc
index 2527631b26..e57f38279f 100644
--- a/elf/passes.cc
+++ b/elf/passes.cc
@@ -1094,22 +1094,6 @@ template <typename E>
 void check_shlib_undefined(Context<E> &ctx) {
   Timer t(ctx, "check_shlib_undefined");
 
-  // Obtain a list of DSOs whose all DT_NEEDED files are known to us.
-  // If a DSO depends on an unknown library, that library may provide
-  // definitions for missing symbols, so we ignore such libraries.
-  std::vector<SharedFile<E> *> dsos = ctx.dsos;
-  std::unordered_set<std::string_view> sonames;
-
-  for (SharedFile<E> *file : dsos)
-    sonames.insert(file->soname);
-
-  std::erase_if(dsos, [&](SharedFile<E> *file) {
-    for (std::string_view needed : file->dt_needed)
-      if (sonames.count(needed) == 0)
-        return true;
-    return false;
-  });
-
   auto is_sparc_register = [](const ElfSym<E> &esym) {
     // Dynamic symbol table for SPARC contains bogus entries which
     // we need to ignore
@@ -1118,17 +1102,28 @@ void check_shlib_undefined(Context<E> &ctx) {
     return false;
   };
 
-  // Check if all undefined symbols have been resolved.
-  for (SharedFile<E> *file : dsos) {
+  // Obtain a list of known shared library names.
+  std::unordered_set<std::string_view> sonames;
+  for (SharedFile<E> *file : ctx.dsos)
+    sonames.insert(file->soname);
+
+  tbb::parallel_for_each(ctx.dsos, [&](SharedFile<E> *file) {
+    // Skip the file if it depends on a file that we know nothing about.
+    // This is because missing symbols may be provided by that unknown file.
+    for (std::string_view needed : file->get_dt_needed(ctx))
+      if (sonames.count(needed) == 0)
+        return;
+
+    // Check if all undefined symbols have been resolved.
     for (i64 i = 0; i < file->elf_syms.size(); i++) {
       const ElfSym<E> &esym = file->elf_syms[i];
       Symbol<E> &sym = *file->symbols[i];
-      if (esym.is_undef() && !esym.is_weak() && !is_sparc_register(esym) &&
-          !sym.file)
+      if (esym.is_undef() && !esym.is_weak() && !sym.file &&
+          !is_sparc_register(esym))
         Error(ctx) << *file << ": --no-allow-shlib-undefined: undefined symbol: "
                    << sym;
     }
-  }
+  });
 }
 
 template <typename E>