From dfc7a90173b25fb4d7cf7e440b34e99bf3b2a1cb Mon Sep 17 00:00:00 2001
From: Joel Rosdahl <joel@rosdahl.net>
Date: Sun, 28 Aug 2022 12:31:41 +0200
Subject: [PATCH] feat: Add support for Clang "--" option

Closes #1149.
---
 src/ArgsInfo.hpp      |  3 +++
 src/argprocessing.cpp |  5 +++++
 src/ccache.cpp        |  4 ++++
 test/suites/base.bash | 13 +++++++++++++
 4 files changed, 25 insertions(+)

diff --git a/src/ArgsInfo.hpp b/src/ArgsInfo.hpp
index 793eb3dc0..92d089b52 100644
--- a/src/ArgsInfo.hpp
+++ b/src/ArgsInfo.hpp
@@ -92,6 +92,9 @@ struct ArgsInfo
   // Whether to strip color codes from diagnostic messages on output.
   bool strip_diagnostics_colors = false;
 
+  // Have we seen --?
+  bool seen_double_dash = false;
+
   // Have we seen -gsplit-dwarf?
   bool seen_split_dwarf = false;
 
diff --git a/src/argprocessing.cpp b/src/argprocessing.cpp
index f1aab5388..404623585 100644
--- a/src/argprocessing.cpp
+++ b/src/argprocessing.cpp
@@ -1027,6 +1027,11 @@ process_option_arg(const Context& ctx,
     return Statistic::none;
   }
 
+  if (args[i] == "--") {
+    args_info.seen_double_dash = true;
+    return Statistic::none;
+  }
+
   // Other options.
   if (args[i][0] == '-') {
     if (compopt_affects_cpp_output(args[i])
diff --git a/src/ccache.cpp b/src/ccache.cpp
index cef6ffab7..5b58f5e6b 100644
--- a/src/ccache.cpp
+++ b/src/ccache.cpp
@@ -1007,6 +1007,10 @@ to_cache(Context& ctx,
     args.push_back(ctx.args_info.output_dia);
   }
 
+  if (ctx.args_info.seen_double_dash) {
+    args.push_back("--");
+  }
+
   if (ctx.config.run_second_cpp()) {
     args.push_back(ctx.args_info.input_file);
   } else {
diff --git a/test/suites/base.bash b/test/suites/base.bash
index 0314ee489..c7272363a 100644
--- a/test/suites/base.bash
+++ b/test/suites/base.bash
@@ -1472,6 +1472,19 @@ EOF
     expect_stat preprocessed_cache_hit 1
     expect_stat cache_miss 1
 
+    # -------------------------------------------------------------------------
+    if touch empty.c && $COMPILER -c -- empty.c 2>/dev/null; then
+        TEST "--"
+
+        $CCACHE_COMPILE -c -- test1.c
+        expect_stat preprocessed_cache_hit 0
+        expect_stat cache_miss 1
+
+        $CCACHE_COMPILE -c -- test1.c
+        expect_stat preprocessed_cache_hit 1
+        expect_stat cache_miss 1
+    fi
+
     # -------------------------------------------------------------------------
     TEST "Handling of compiler-only arguments"
 
-- 
2.47.2