From 2a08c781d11ea5ca8b312c5f5cf694fd3e51793a Mon Sep 17 00:00:00 2001
From: Arnaud Vrac <avrac@freebox.fr>
Date: Mon, 7 Feb 2022 23:04:58 +0100
Subject: [PATCH] [ELF] implement -Y flag

---
 docs/mold.1    | 7 +++++++
 elf/cmdline.cc | 8 ++++++++
 2 files changed, 15 insertions(+)

diff --git a/docs/mold.1 b/docs/mold.1
index 64210a6150..ab2f165ab1 100644
--- a/docs/mold.1
+++ b/docs/mold.1
@@ -320,6 +320,13 @@ Temporary local symbols are local symbols starting with
 Compilers usually generate such symbols for unnamed program elements such as \
 string literals or floating-point literals.
 .Pp
+.It Fl Y Ns Ar dir
+Add
+.Ar dir
+to the list of default search paths from which
+.Nm
+searches libraries for the \fB-l\fR option.
+.Pp
 .It Fl e Ar symbol , Fl -entry Ns = Ns Ar symbol
 Use
 .Ar symbol
diff --git a/elf/cmdline.cc b/elf/cmdline.cc
index 6210bb5e79..5310c06f36 100644
--- a/elf/cmdline.cc
+++ b/elf/cmdline.cc
@@ -39,6 +39,7 @@ static const char helpmsg[] = R"(
   -S, --strip-debug           Strip .debug_* sections
   -T FILE, --script FILE      Read linker script
   -X, --discard-locals        Discard temporary local symbols
+  -Y DIR                      Add DIR to default library search path
   -e SYMBOL, --entry SYMBOL   Set program entry point
   -f SHLIB, --auxiliary SHLIB Set DT_AUXILIARY to the specified value
   -h LIBNAME, --soname LIBNAME
@@ -338,6 +339,7 @@ std::vector<std::string> parse_nonpositional_args(Context<E> &ctx) {
   ctx.page_size = E::page_size;
   ctx.arg.color_diagnostics = isatty(STDERR_FILENO);
 
+  std::vector<std::string> default_library_paths;
   bool version_shown = false;
   bool warn_shared_textrel = false;
 
@@ -533,6 +535,8 @@ std::vector<std::string> parse_nonpositional_args(Context<E> &ctx) {
       ctx.arg.filler = parse_hex(ctx, "filler", arg);
     } else if (read_arg("L") || read_arg("library-path")) {
       ctx.arg.library_paths.push_back(std::string(arg));
+    } else if (read_arg("Y")) {
+      default_library_paths.push_back(std::string(arg));
     } else if (read_arg("sysroot")) {
       ctx.arg.sysroot = arg;
     } else if (read_arg("unique")) {
@@ -998,6 +1002,10 @@ std::vector<std::string> parse_nonpositional_args(Context<E> &ctx) {
     }
   }
 
+  ctx.arg.library_paths.insert(ctx.arg.library_paths.end(),
+          default_library_paths.begin(),
+          default_library_paths.end());
+
   if (!ctx.arg.sysroot.empty()) {
     for (std::string &path : ctx.arg.library_paths) {
       if (std::string_view(path).starts_with('='))