From 6f04ef9cf2be6946cd1ed66603285b9523ce44c0 Mon Sep 17 00:00:00 2001
From: Rui Ueyama <ruiu@bluewhale.systems>
Date: Mon, 6 Jun 2022 20:22:53 +0800
Subject: [PATCH] [Mach-O] Handle $ld$install_name$ symbols

---
 macho/tapi.cc                  | 11 ++++++++
 test/macho/tbd-install-name.sh | 49 ++++++++++++++++++++++++++++++++++
 2 files changed, 60 insertions(+)
 create mode 100755 test/macho/tbd-install-name.sh

diff --git a/macho/tapi.cc b/macho/tapi.cc
index ac51ba69..1735b81d 100644
--- a/macho/tapi.cc
+++ b/macho/tapi.cc
@@ -173,6 +173,17 @@ static void interpret_ld_symbols(Context<E> &ctx, TextDylib &tbd) {
         hidden_syms.insert(m[2]);
       continue;
     }
+
+    // $ld$install_name$os_version$name changes the install name to a
+    // given name.
+    static std::regex
+      install_name_re(R"(\$ld\$install_name\$os([\d.]+)\$(.+))", flags);
+
+    if (std::regex_match(name, m, install_name_re)) {
+      if (ctx.arg.platform_min_version == parse_version(m[1]))
+        tbd.install_name = save_string(ctx, m[2]);
+      continue;
+    }
   }
 
   for (std::string_view s : tbd.exports)
diff --git a/test/macho/tbd-install-name.sh b/test/macho/tbd-install-name.sh
new file mode 100755
index 00000000..680b5452
--- /dev/null
+++ b/test/macho/tbd-install-name.sh
@@ -0,0 +1,49 @@
+#!/bin/bash
+export LC_ALL=C
+set -e
+CC="${TEST_CC:-cc}"
+CXX="${TEST_CXX:-c++}"
+GCC="${TEST_GCC:-gcc}"
+GXX="${TEST_GXX:-g++}"
+OBJDUMP="${OBJDUMP:-objdump}"
+MACHINE="${MACHINE:-$(uname -m)}"
+testname=$(basename "$0" .sh)
+echo -n "Testing $testname ... "
+cd "$(dirname "$0")"/../..
+t=out/test/macho/$testname
+mkdir -p $t
+
+cat > $t/libfoo.tbd <<'EOF'
+--- !tapi-tbd
+tbd-version:     4
+targets:         [ x86_64-macos, arm64-macos ]
+uuids:
+  - target:          x86_64-macos
+    value:           00000000-0000-0000-0000-000000000000
+  - target:          arm64-macos
+    value:           00000000-0000-0000-0000-000000000000
+install-name:    '/foo'
+current-version: 0
+compatibility-version: 0
+exports:
+  - targets:         [ x86_64-macos, arm64-macos ]
+    symbols:         [ '$ld$install_name$os25.0$/bar', _foo ]
+...
+EOF
+
+cat <<EOF | clang -o $t/a.o -c -xc -
+void foo();
+int main() { foo(); }
+EOF
+
+clang --ld-path=./ld64 -o $t/exe1 $t/libfoo.tbd $t/a.o \
+  -Wl,-platform_version,macos,20.0,20.0 >& /dev/null
+
+otool -L $t/exe1 | grep -q /foo
+
+clang --ld-path=./ld64 -o $t/exe2 $t/libfoo.tbd $t/a.o \
+  -Wl,-platform_version,macos,25.0,21.0 >& /dev/null
+
+otool -L $t/exe2 | grep -q /bar
+
+echo OK