glibc: include ld symbols and proper soname for ld

src-self-hosted/stage2.zig

@@ -909,6 +909,7 @@ const Stage2Target = extern struct {
     os_builtin_str: ?[*:0]const u8,
 
     dynamic_linker: ?[*:0]const u8,
+    standard_dynamic_linker_path: ?[*:0]const u8,
 
     fn fromTarget(self: *Stage2Target, cross_target: CrossTarget) !void {
         const allocator = std.heap.c_allocator;
@@ -1119,6 +1120,12 @@ const Stage2Target = extern struct {
             }
         };
 
+        const std_dl = target.standardDynamicLinkerPath();
+        const std_dl_z = if (std_dl.get()) |dl|
+            (try mem.dupeZ(std.heap.c_allocator, u8, dl)).ptr
+        else
+            null;
+
         const cache_hash_slice = cache_hash.toOwnedSlice();
         self.* = .{
             .arch = @enumToInt(target.cpu.arch) + 1, // skip over ZigLLVM_UnknownArch
@@ -1134,6 +1141,7 @@ const Stage2Target = extern struct {
             .is_native = cross_target.isNative(),
             .glibc_or_darwin_version = glibc_or_darwin_version,
             .dynamic_linker = dynamic_linker,
+            .standard_dynamic_linker_path = std_dl_z,
         };
     }
 };

src/all_types.hpp

@@ -2267,6 +2267,7 @@ struct CodeGen {
     Buf *zig_lib_dir;
     Buf *zig_std_dir;
     Buf *version_script_path;
+    Buf *override_soname;
 
     const char **llvm_argv;
     size_t llvm_argv_len;

src/codegen.cpp

@@ -10510,6 +10510,7 @@ static Error check_cache(CodeGen *g, Buf *manifest_dir, Buf *digest) {
         cache_str(ch, g->libc->kernel32_lib_dir);
     }
     cache_buf_opt(ch, g->version_script_path);
+    cache_buf_opt(ch, g->override_soname);
 
     // gen_c_objects appends objects to g->link_objects which we want to include in the hash
     gen_c_objects(g);

src/glibc.cpp

@@ -16,6 +16,7 @@ static const ZigGLibCLib glibc_libs[] = {
     {"pthread", 0},
     {"dl", 2},
     {"rt", 1},
+    {"ld", 2},
 };
 
 Error glibc_load_metadata(ZigGLibCAbi **out_result, Buf *zig_lib_dir, bool verbose) {
@@ -330,6 +331,8 @@ Error glibc_build_dummies_and_maps(CodeGen *g, const ZigGLibCAbi *glibc_abi, con
             return err;
         }
 
+        bool is_ld = (strcmp(lib->name, "ld") == 0);
+
         CodeGen *child_gen = create_child_codegen(g, zig_file_path, OutTypeLib, nullptr, lib->name, progress_node);
         codegen_set_lib_version(child_gen, lib->sover, 0, 0);
         child_gen->is_dynamic = true;
@@ -337,6 +340,13 @@ Error glibc_build_dummies_and_maps(CodeGen *g, const ZigGLibCAbi *glibc_abi, con
         child_gen->version_script_path = map_file_path;
         child_gen->enable_cache = false;
         child_gen->output_dir = dummy_dir;
+        if (is_ld) {
+            assert(g->zig_target->standard_dynamic_linker_path != nullptr);
+            Buf *ld_basename = buf_alloc();
+            os_path_split(buf_create_from_str(g->zig_target->standard_dynamic_linker_path),
+                    nullptr, ld_basename);
+            child_gen->override_soname = ld_basename;
+        }
         codegen_build_and_link(child_gen);
     }
 

src/link.cpp

@@ -1651,7 +1651,6 @@ static void construct_linker_job_elf(LinkJob *lj) {
 
     bool is_lib = g->out_type == OutTypeLib;
     bool is_dyn_lib = g->is_dynamic && is_lib;
-    Buf *soname = nullptr;
     if (!g->have_dynamic_link) {
         if (g->zig_target->arch == ZigLLVM_arm || g->zig_target->arch == ZigLLVM_armeb ||
             g->zig_target->arch == ZigLLVM_thumb || g->zig_target->arch == ZigLLVM_thumbeb)
@@ -1662,15 +1661,13 @@ static void construct_linker_job_elf(LinkJob *lj) {
         }
     } else if (is_dyn_lib) {
         lj->args.append("-shared");
-
-        assert(buf_len(&g->bin_file_output_path) != 0);
-        soname = buf_sprintf("lib%s.so.%" ZIG_PRI_usize, buf_ptr(g->root_out_name), g->version_major);
     }
 
     if (target_requires_pie(g->zig_target) && g->out_type == OutTypeExe) {
         lj->args.append("-pie");
     }
 
+    assert(buf_len(&g->bin_file_output_path) != 0);
     lj->args.append("-o");
     lj->args.append(buf_ptr(&g->bin_file_output_path));
 
@@ -1740,6 +1737,9 @@ static void construct_linker_job_elf(LinkJob *lj) {
     }
 
     if (is_dyn_lib) {
+        Buf *soname = (g->override_soname == nullptr) ?
+            buf_sprintf("lib%s.so.%" ZIG_PRI_usize, buf_ptr(g->root_out_name), g->version_major) :
+            g->override_soname;
         lj->args.append("-soname");
         lj->args.append(buf_ptr(soname));
 

src/stage2.h

@@ -291,6 +291,7 @@ struct ZigTarget {
     size_t cache_hash_len;
     const char *os_builtin_str;
     const char *dynamic_linker;
+    const char *standard_dynamic_linker_path;
 };
 
 // ABI warning