From 0b7bef19b6b43d66667f8bd35701fa45ebee7f16 Mon Sep 17 00:00:00 2001
From: Jakub Konka <kubkon@jakubkonka.com>
Date: Thu, 14 Mar 2024 16:38:27 +0100
Subject: [PATCH] macho: fix a sad typo in calculating the address of a TLV
 pointer

---
 src/MachO/synthetic.zig |  2 +-
 test/macho.zig          | 67 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+), 1 deletion(-)

diff --git a/src/MachO/synthetic.zig b/src/MachO/synthetic.zig
index d99aee56..1bef39ca 100644
--- a/src/MachO/synthetic.zig
+++ b/src/MachO/synthetic.zig
@@ -412,7 +412,7 @@ pub const TlvPtrSection = struct {
     pub fn getAddress(tlv: TlvPtrSection, index: Index, macho_file: *MachO) u64 {
         assert(index < tlv.symbols.items.len);
         const header = macho_file.sections.items(.header)[macho_file.tlv_ptr_sect_index.?];
-        return header.addr + index * @sizeOf(u64) * 3;
+        return header.addr + index * @sizeOf(u64);
     }
 
     pub fn size(tlv: TlvPtrSection) usize {
diff --git a/test/macho.zig b/test/macho.zig
index 3e9ecb1b..148de705 100644
--- a/test/macho.zig
+++ b/test/macho.zig
@@ -70,6 +70,7 @@ pub fn addMachOTests(b: *Build, options: common.Options) *Step {
     macho_step.dependOn(testThunks(b, opts));
     macho_step.dependOn(testTls(b, opts));
     macho_step.dependOn(testTlsLargeTbss(b, opts));
+    macho_step.dependOn(testTlsPointers(b, opts));
     macho_step.dependOn(testTwoLevelNamespace(b, opts));
     macho_step.dependOn(testUndefinedFlag(b, opts));
     macho_step.dependOn(testUnwindInfo(b, opts));
@@ -2922,6 +2923,72 @@ fn testTlsLargeTbss(b: *Build, opts: Options) *Step {
     return test_step;
 }
 
+// https://github.com/ziglang/zig/issues/19221
+fn testTlsPointers(b: *Build, opts: Options) *Step {
+    const test_step = b.step("test-macho-tls-pointers", "");
+
+    const includes = WriteFile.create(b);
+    _ = includes.add("foo.h",
+        \\template<typename just4fun>
+        \\struct Foo {
+        \\  
+        \\public:
+        \\  static int getVar() {
+        \\  static int thread_local var = 0;
+        \\  ++var;
+        \\  return var;
+        \\}
+        \\};
+    );
+
+    const bar_o = cc(b, "bar.o", opts);
+    bar_o.addCppSource(
+        \\#include "foo.h"
+        \\int bar() {
+        \\  int v1 = Foo<int>::getVar();
+        \\  return v1;
+        \\}
+    );
+    bar_o.addArgs(&.{ "-c", "-std=c++17" });
+    bar_o.addPrefixedDirectorySource("-I", includes.getDirectory());
+
+    const baz_o = cc(b, "baz.o", opts);
+    baz_o.addCppSource(
+        \\#include "foo.h"
+        \\int baz() {
+        \\  int v1 = Foo<unsigned>::getVar();
+        \\  return v1;
+        \\}
+    );
+    baz_o.addArgs(&.{ "-c", "-std=c++17" });
+    baz_o.addPrefixedDirectorySource("-I", includes.getDirectory());
+
+    const main_o = cc(b, "main.o", opts);
+    main_o.addCppSource(
+        \\extern int bar();
+        \\extern int baz();
+        \\int main() {
+        \\  int v1 = bar();
+        \\  int v2 = baz();
+        \\  return v1 != v2;
+        \\}
+    );
+    main_o.addArgs(&.{ "-c", "-std=c++17" });
+    main_o.addPrefixedDirectorySource("-I", includes.getDirectory());
+
+    const exe = cc(b, "a.out", opts);
+    exe.addFileSource(bar_o.getFile());
+    exe.addFileSource(baz_o.getFile());
+    exe.addFileSource(main_o.getFile());
+    exe.addArg("-lc++");
+
+    const run = exe.run();
+    run.expectExitCode(0);
+    test_step.dependOn(run.step());
+
+    return test_step;
+}
+
 fn testUndefinedFlag(b: *Build, opts: Options) *Step {
     const test_step = b.step("test-macho-undefined-flag", "");