From d9fa9912d0098fcfc45a00bfa21850171eee58a0 Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Tue, 4 Apr 2023 02:18:40 -0400
Subject: [PATCH 01/11] Disabled unused but set variable warnings in
 CMakeLists.txt

---
 CMakeLists.txt                 | 3 +++
 test/test_lang_bind_helper.cpp | 6 +++---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 03d87cf16ac..49b551b399e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -112,6 +112,9 @@ else()
     # compilers that we still support. It is also harmless, unlike pessimizing moves.
     add_cxx_flag_if_supported(-Wno-redundant-move)
 
+    # MacOS Clang 14.0.3 started enabling unused-but-set-variables by default
+    add_cxx_flag_if_supported(-Wno-unused-but-set-variable)
+
     # Ninja buffers output so we need to tell the compiler to use colors even though stdout isn't a tty.
     if("${CMAKE_GENERATOR}" STREQUAL "Ninja")
         add_cxx_flag_if_supported(-fdiagnostics-color)
diff --git a/test/test_lang_bind_helper.cpp b/test/test_lang_bind_helper.cpp
index 7335fc66996..cc98b6f353e 100644
--- a/test/test_lang_bind_helper.cpp
+++ b/test/test_lang_bind_helper.cpp
@@ -3986,7 +3986,7 @@ struct HandoverControl {
         while (m_handover != nullptr)
             m_changed.wait(lg);
         // std::cout << " -- put " << h << std::endl;
-        m_handover = move(h);
+        m_handover = std::move(h);
         m_changed.notify_all();
     }
     void get(std::unique_ptr<T>& h)
@@ -3996,7 +3996,7 @@ struct HandoverControl {
         while (m_handover == nullptr)
             m_changed.wait(lg);
         // std::cout << " -- get " << m_handover << std::endl;
-        h = move(m_handover);
+        h = std::move(m_handover);
         m_handover = nullptr;
         m_changed.notify_all();
     }
@@ -4005,7 +4005,7 @@ struct HandoverControl {
         LockGuard lg(m_lock);
         if (m_handover == nullptr)
             return false;
-        h = move(m_handover);
+        h = std::move(m_handover);
         m_handover = nullptr;
         m_changed.notify_all();
         return true;

From 71bb665c65e881424d7388322c8f1b9c10e28e67 Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Tue, 4 Apr 2023 02:23:17 -0400
Subject: [PATCH 02/11] Updated changelog

---
 CHANGELOG.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8d1a1f99b49..f5e09484d2e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,7 +17,7 @@
 -----------
 
 ### Internals
-* None.
+* Fix compiler warnings with MacOS Clang 14.0.3 ([PR #6467](https://github.com/realm/realm-core/pull/6467))
 
 ----------------------------------------------
 

From 74c74f4331f498517e63fef8257cf45f0c4a00f7 Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Tue, 4 Apr 2023 10:06:13 -0400
Subject: [PATCH 03/11] Fix warnings in existing files

---
 test/test_query.cpp  | 2 --
 test/test_shared.cpp | 3 ---
 2 files changed, 5 deletions(-)

diff --git a/test/test_query.cpp b/test/test_query.cpp
index 72ac7996648..b25379965c0 100644
--- a/test/test_query.cpp
+++ b/test/test_query.cpp
@@ -2904,7 +2904,6 @@ TEST_IF(Query_StrIndex3, TEST_DURATION > 0)
 
         std::vector<ObjKey> vec;
 
-        size_t n = 0;
 #if defined REALM_DEBUG || REALM_ANDROID
         for (int i = 0; i < 4; i++) {
 #else
@@ -2924,7 +2923,6 @@ TEST_IF(Query_StrIndex3, TEST_DURATION > 0)
                         ObjKey key =
                             ttt.create_object().set_all(0, longstrings ? "AAAAAAAAAAAAAAAAAAAAAAAA" : "AA").get_key();
                         if (!longstrings) {
-                            n++;
                             vec.push_back(key);
                         }
                     }
diff --git a/test/test_shared.cpp b/test/test_shared.cpp
index 4a64de052ed..a1a113408d8 100644
--- a/test/test_shared.cpp
+++ b/test/test_shared.cpp
@@ -1841,13 +1841,10 @@ TEST(Shared_StringIndexBug3)
     }
 
     Random random(random_int<unsigned long>()); // Seed from slow global generator
-    size_t transactions = 0;
     std::vector<ObjKey> keys;
     for (size_t n = 0; n < 100; ++n) {
         const uint64_t action = random.draw_int_mod(1000);
 
-        transactions++;
-
         if (action <= 500) {
             // delete random user
             auto tr = db->start_write();

From 6460bc9f471c9cfd55ce89c9f6a33364be7cf506 Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Tue, 4 Apr 2023 13:15:01 -0400
Subject: [PATCH 04/11] Remove global no-unused-but-set warnings and add back
 for parser files

---
 CMakeLists.txt                  | 14 ++++++++++++--
 src/realm/parser/CMakeLists.txt | 13 ++++++++++++-
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 49b551b399e..a2fd7b9153f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,6 +57,17 @@ function(add_cxx_flag_if_supported flag)
     endif()
 endfunction()
 
+function(check_if_cxx_compiler_flag_supported flag out_var)
+    if(flag MATCHES "^-Wno-")
+        # Compilers ignore unknown -Wno-foo flags, so look for -Wfoo instead.
+        string(REPLACE "-Wno-" "-W" check_flag ${flag})
+    else()
+        set(check_flag ${flag})
+    endif()
+
+    check_cxx_compiler_flag(${check_flag} ${out_var})
+endfunction()
+
 function(use_faster_linker)
     # If a linker has already been set, don't override.
     if ("${CMAKE_EXE_LINKER_FLAGS}" MATCHES "-fuse-ld=")
@@ -112,8 +123,7 @@ else()
     # compilers that we still support. It is also harmless, unlike pessimizing moves.
     add_cxx_flag_if_supported(-Wno-redundant-move)
 
-    # MacOS Clang 14.0.3 started enabling unused-but-set-variables by default
-    add_cxx_flag_if_supported(-Wno-unused-but-set-variable)
+    check_if_cxx_compiler_flag_supported(-Wno-unused-but-set-variable HAS-Wno-unused-but-set-variable)
 
     # Ninja buffers output so we need to tell the compiler to use colors even though stdout isn't a tty.
     if("${CMAKE_GENERATOR}" STREQUAL "Ninja")
diff --git a/src/realm/parser/CMakeLists.txt b/src/realm/parser/CMakeLists.txt
index 39f2b42d786..9ca9e3a3998 100644
--- a/src/realm/parser/CMakeLists.txt
+++ b/src/realm/parser/CMakeLists.txt
@@ -33,6 +33,9 @@ endif()
 set(REALM_PARSER_SOURCES
     driver.cpp
     keypath_mapping.cpp
+) # REALM_PARSER_SOURCES
+
+set(REALM_PARSER_GENERAED
     generated/query_flex.cpp
     generated/query_bison.cpp
 ) # REALM_PARSER_SOURCES
@@ -56,13 +59,21 @@ set(REALM_PARSER_EXTRAS
     query_flex.ll
 )
 
+# Add custom warning flags for generated parser files
+if(HAS-Wno-unused-but-set-variable)
+    foreach(SRC_ IN LISTS REALM_PARSER_GENERAED)
+        get_filename_component(SRC_BASENAME_ ${SRC_} NAME_WE)
+        set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "-Wno-unused-but-set-variable")
+    endforeach()
+endif()
+
 if(MSVC)
     set_source_files_properties(generated/query_flex.cpp PROPERTIES COMPILE_OPTIONS "/wd4018")
 else()
     set_source_files_properties(generated/query_flex.cpp PROPERTIES COMPILE_OPTIONS "-Wno-unreachable-code;-Wno-sign-compare")
 endif()
 
-add_library(QueryParser STATIC ${REALM_PARSER_SOURCES} ${REALM_PARSER_HEADERS} ${REALM_PARSER_EXTRAS})
+add_library(QueryParser STATIC ${REALM_PARSER_SOURCES} ${REALM_PARSER_GENERAED} ${REALM_PARSER_HEADERS} ${REALM_PARSER_EXTRAS})
 add_library(realm-parser ALIAS QueryParser)
 add_library(Realm::QueryParser ALIAS QueryParser)
 target_link_libraries(QueryParser PUBLIC Storage)

From 8bb2ca7bcf54292c55d87f031e503276f429765e Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Tue, 4 Apr 2023 13:45:16 -0400
Subject: [PATCH 05/11] Disable the unused-but-set warning on the 3rd party
 Catch library

---
 CMakeLists.txt          | 2 +-
 external/CMakeLists.txt | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)
 create mode 100644 external/CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index a2fd7b9153f..e90ba63163a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -313,7 +313,7 @@ elseif(APPLE AND NOT CMAKE_SYSTEM_NAME STREQUAL "Darwin")
 endif()
 set(CATCH_CONFIG_ENABLE_ALL_STRINGMAKERS ON CACHE BOOL "Enable Catch2's optional standard library stringmakers")
 
-add_subdirectory(external/catch EXCLUDE_FROM_ALL)
+add_subdirectory(external EXCLUDE_FROM_ALL)
 
 # Cmake does not let us easily set the deployment target per-target, but Catch2
 # can use modern features because we only run tests on recent OS versions.
diff --git a/external/CMakeLists.txt b/external/CMakeLists.txt
new file mode 100644
index 00000000000..114b722f220
--- /dev/null
+++ b/external/CMakeLists.txt
@@ -0,0 +1,4 @@
+cmake_minimum_required(VERSION 3.15)
+
+add_cxx_flag_if_supported(-Wno-unused-but-set-variable)
+add_subdirectory(catch)

From e7292f53a656463e53416d86ad95bf30f75c1386 Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Wed, 5 Apr 2023 10:13:44 -0400
Subject: [PATCH 06/11] Updates from review and added
 append_source_file_compile_options function

---
 CMakeLists.txt                  | 24 ++++++++++++------------
 src/realm/parser/CMakeLists.txt | 16 ++++++++++------
 test/CMakeLists.txt             |  3 ++-
 3 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e90ba63163a..67ee7e1b06d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -43,7 +43,7 @@ elseif(APPLE)
     set(CMAKE_VISIBILITY_INLINES_HIDDEN 1)
 endif()
 
-function(add_cxx_flag_if_supported flag)
+function(check_if_cxx_compiler_flag_supported flag out_var)
     if(flag MATCHES "^-Wno-")
         # Compilers ignore unknown -Wno-foo flags, so look for -Wfoo instead.
         string(REPLACE "-Wno-" "-W" check_flag ${flag})
@@ -51,21 +51,23 @@ function(add_cxx_flag_if_supported flag)
         set(check_flag ${flag})
     endif()
 
-    check_cxx_compiler_flag(${check_flag} HAVE${check_flag})
-    if(HAVE${check_flag})
+    check_cxx_compiler_flag(${check_flag} ${out_var})
+endfunction()
+
+function(add_cxx_flag_if_supported flag)
+    check_if_cxx_compiler_flag_supported(${flag} HAVE${flag})
+    if(HAVE${flag})
         add_compile_options($<$<COMPILE_LANGUAGE:CXX>:${flag}>)
     endif()
 endfunction()
 
-function(check_if_cxx_compiler_flag_supported flag out_var)
-    if(flag MATCHES "^-Wno-")
-        # Compilers ignore unknown -Wno-foo flags, so look for -Wfoo instead.
-        string(REPLACE "-Wno-" "-W" check_flag ${flag})
+function(append_source_file_compile_options file property)
+    get_source_file_property(SRC_PROPS_${file} ${file} COMPILE_OPTIONS)
+    if ("${SRC_PROPS_${file}}" STREQUAL "NOTFOUND" OR "${SRC_PROPS_${file}}" STREQUAL "")
+        set_source_files_properties(${file} PROPERTIES COMPILE_OPTIONS "${property}")
     else()
-        set(check_flag ${flag})
+        set_source_files_properties(${file} PROPERTIES COMPILE_OPTIONS "${SRC_PROPS_${file}};${property}")
     endif()
-
-    check_cxx_compiler_flag(${check_flag} ${out_var})
 endfunction()
 
 function(use_faster_linker)
@@ -123,8 +125,6 @@ else()
     # compilers that we still support. It is also harmless, unlike pessimizing moves.
     add_cxx_flag_if_supported(-Wno-redundant-move)
 
-    check_if_cxx_compiler_flag_supported(-Wno-unused-but-set-variable HAS-Wno-unused-but-set-variable)
-
     # Ninja buffers output so we need to tell the compiler to use colors even though stdout isn't a tty.
     if("${CMAKE_GENERATOR}" STREQUAL "Ninja")
         add_cxx_flag_if_supported(-fdiagnostics-color)
diff --git a/src/realm/parser/CMakeLists.txt b/src/realm/parser/CMakeLists.txt
index 9ca9e3a3998..9738d50ab66 100644
--- a/src/realm/parser/CMakeLists.txt
+++ b/src/realm/parser/CMakeLists.txt
@@ -59,18 +59,22 @@ set(REALM_PARSER_EXTRAS
     query_flex.ll
 )
 
-# Add custom warning flags for generated parser files
-if(HAS-Wno-unused-but-set-variable)
+# Add custom warning flags for generated parser files if the flag is supported
+set(PARSER_COMPILE_EXTRA -Wno-unused-but-set-variable)
+
+check_if_cxx_compiler_flag_supported(${PARSER_COMPILE_EXTRA} HAVE${PARSER_COMPILE_EXTRA})
+
+if(HAVE${PARSER_COMPILE_EXTRA})
     foreach(SRC_ IN LISTS REALM_PARSER_GENERAED)
-        get_filename_component(SRC_BASENAME_ ${SRC_} NAME_WE)
-        set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "-Wno-unused-but-set-variable")
+        append_source_file_compile_options(${SRC_} "${PARSER_COMPILE_EXTRA}")
     endforeach()
 endif()
 
+# Append additional compile options to the generated/query_flex.cpp file
 if(MSVC)
-    set_source_files_properties(generated/query_flex.cpp PROPERTIES COMPILE_OPTIONS "/wd4018")
+    append_source_file_compile_options(generated/query_flex.cpp "/wd4018")
 else()
-    set_source_files_properties(generated/query_flex.cpp PROPERTIES COMPILE_OPTIONS "-Wno-unreachable-code;-Wno-sign-compare")
+    append_source_file_compile_options(generated/query_flex.cpp "-Wno-unreachable-code;-Wno-sign-compare")
 endif()
 
 add_library(QueryParser STATIC ${REALM_PARSER_SOURCES} ${REALM_PARSER_GENERAED} ${REALM_PARSER_HEADERS} ${REALM_PARSER_EXTRAS})
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index f5ee6bcc9a8..bb11359e37d 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -122,7 +122,8 @@ set(CORE_TESTS ${CORE_TEST_SOURCES} ${LARGE_TEST_SOURCES} ${FUZZY_TEST_SOURCES})
 # FIXME: Benchmarks
 
 if (MSVC)
-    set_source_files_properties(test_query.cpp test_query_big.cpp PROPERTIES COMPILE_FLAGS /bigobj)
+    append_source_file_compile_options(test_query.cpp /bigobj)
+    append_source_file_compile_options(test_query_big.cpp /bigobj)
 endif()
 
 # Resources required for running the tests

From ed0edf97ae5c0b934946a0346af2a2cf72f90bde Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Wed, 5 Apr 2023 16:05:38 -0400
Subject: [PATCH 07/11] Updates from review - beefed up append compile options
 function

---
 CMakeLists.txt                  | 32 ++++++++++++++++++++++++++------
 src/realm/parser/CMakeLists.txt | 18 +++++-------------
 test/CMakeLists.txt             |  3 +--
 3 files changed, 32 insertions(+), 21 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 67ee7e1b06d..47fc87593b2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -61,13 +61,33 @@ function(add_cxx_flag_if_supported flag)
     endif()
 endfunction()
 
-function(append_source_file_compile_options file property)
-    get_source_file_property(SRC_PROPS_${file} ${file} COMPILE_OPTIONS)
-    if ("${SRC_PROPS_${file}}" STREQUAL "NOTFOUND" OR "${SRC_PROPS_${file}}" STREQUAL "")
-        set_source_files_properties(${file} PROPERTIES COMPILE_OPTIONS "${property}")
-    else()
-        set_source_files_properties(${file} PROPERTIES COMPILE_OPTIONS "${SRC_PROPS_${file}};${property}")
+
+# Usage: append_source_file_compile_options(FILE <file1> FLAG <flag>)
+#    or: append_source_file_compile_options(FILES <file1> <file2>... FLAGS <flag1> <flag2>...)
+function(append_source_file_compile_options)
+    set(options)
+    set(args)
+    set(list_args FILES FLAGS)
+    cmake_parse_arguments(append_options "${options}" "${args}" "${list_args}" ${ARGN})
+    if ("${append_options_FILES}" STREQUAL "")
+        message(FATAL_ERROR "Missing FILES argument for append_source_file_compile_options")
+    endif()
+    if ("${append_options_FLAGS}" STREQUAL "")
+        message(FATAL_ERROR "Missing FLAGS argument for append_source_file_compile_options")
     endif()
+    foreach(FLAG_ IN LISTS append_options_FLAGS)
+        check_if_cxx_compiler_flag_supported(${FLAG_} HAVE${FLAG_})
+        if (HAVE${FLAG_})
+            foreach(SRC_ IN LISTS append_options_FILES)
+                get_source_file_property(SRC_PROPS_${SRC_} ${SRC_} COMPILE_OPTIONS)
+                if ("${SRC_PROPS_${SRC_}}" STREQUAL "NOTFOUND" OR "${SRC_PROPS_${SRC_}}" STREQUAL "")
+                    set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${FLAG_}")
+                elseif(NOT "${FLAG_}" IN_LIST SRC_PROPS_${SRC_})
+                    set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${SRC_PROPS_${SRC_}};${FLAG_}")
+                endif()
+            endforeach()
+        endif()
+    endforeach()
 endfunction()
 
 function(use_faster_linker)
diff --git a/src/realm/parser/CMakeLists.txt b/src/realm/parser/CMakeLists.txt
index 9738d50ab66..12dda0ada14 100644
--- a/src/realm/parser/CMakeLists.txt
+++ b/src/realm/parser/CMakeLists.txt
@@ -35,7 +35,7 @@ set(REALM_PARSER_SOURCES
     keypath_mapping.cpp
 ) # REALM_PARSER_SOURCES
 
-set(REALM_PARSER_GENERAED
+set(REALM_PARSER_GENERATED
     generated/query_flex.cpp
     generated/query_bison.cpp
 ) # REALM_PARSER_SOURCES
@@ -60,24 +60,16 @@ set(REALM_PARSER_EXTRAS
 )
 
 # Add custom warning flags for generated parser files if the flag is supported
-set(PARSER_COMPILE_EXTRA -Wno-unused-but-set-variable)
-
-check_if_cxx_compiler_flag_supported(${PARSER_COMPILE_EXTRA} HAVE${PARSER_COMPILE_EXTRA})
-
-if(HAVE${PARSER_COMPILE_EXTRA})
-    foreach(SRC_ IN LISTS REALM_PARSER_GENERAED)
-        append_source_file_compile_options(${SRC_} "${PARSER_COMPILE_EXTRA}")
-    endforeach()
-endif()
+append_source_file_compile_options(FILES ${REALM_PARSER_GENERATED} FLAGS -Wno-unused-but-set-variable)
 
 # Append additional compile options to the generated/query_flex.cpp file
 if(MSVC)
-    append_source_file_compile_options(generated/query_flex.cpp "/wd4018")
+    append_source_file_compile_options(FILES generated/query_flex.cpp FLAGS /wd4018)
 else()
-    append_source_file_compile_options(generated/query_flex.cpp "-Wno-unreachable-code;-Wno-sign-compare")
+    append_source_file_compile_options(FILES generated/query_flex.cpp FLAGS -Wno-unreachable-code -Wno-sign-compare)
 endif()
 
-add_library(QueryParser STATIC ${REALM_PARSER_SOURCES} ${REALM_PARSER_GENERAED} ${REALM_PARSER_HEADERS} ${REALM_PARSER_EXTRAS})
+add_library(QueryParser STATIC ${REALM_PARSER_SOURCES} ${REALM_PARSER_GENERATED} ${REALM_PARSER_HEADERS} ${REALM_PARSER_EXTRAS})
 add_library(realm-parser ALIAS QueryParser)
 add_library(Realm::QueryParser ALIAS QueryParser)
 target_link_libraries(QueryParser PUBLIC Storage)
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index bb11359e37d..00dee4e77b3 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -122,8 +122,7 @@ set(CORE_TESTS ${CORE_TEST_SOURCES} ${LARGE_TEST_SOURCES} ${FUZZY_TEST_SOURCES})
 # FIXME: Benchmarks
 
 if (MSVC)
-    append_source_file_compile_options(test_query.cpp /bigobj)
-    append_source_file_compile_options(test_query_big.cpp /bigobj)
+    append_source_file_compile_options(FILES test_query.cpp test_query_big.cpp FLAGS /bigobj)
 endif()
 
 # Resources required for running the tests

From 9563e27cb268b75dc3533bbfff7d785354459322 Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Wed, 5 Apr 2023 16:38:52 -0400
Subject: [PATCH 08/11] Some simplification of append compile options function

---
 CMakeLists.txt | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 47fc87593b2..25d4016d5c1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -62,28 +62,27 @@ function(add_cxx_flag_if_supported flag)
 endfunction()
 
 
-# Usage: append_source_file_compile_options(FILE <file1> FLAG <flag>)
-#    or: append_source_file_compile_options(FILES <file1> <file2>... FLAGS <flag1> <flag2>...)
+# Usage: append_source_file_compile_options(FILES <file1>[ <file2>...] FLAGS <flag1>[ <flag2>...])
 function(append_source_file_compile_options)
     set(options)
     set(args)
     set(list_args FILES FLAGS)
     cmake_parse_arguments(append_options "${options}" "${args}" "${list_args}" ${ARGN})
-    if ("${append_options_FILES}" STREQUAL "")
+    if (NOT append_options_FILES)
         message(FATAL_ERROR "Missing FILES argument for append_source_file_compile_options")
     endif()
-    if ("${append_options_FLAGS}" STREQUAL "")
+    if (NOT append_options_FLAGS)
         message(FATAL_ERROR "Missing FLAGS argument for append_source_file_compile_options")
     endif()
     foreach(FLAG_ IN LISTS append_options_FLAGS)
-        check_if_cxx_compiler_flag_supported(${FLAG_} HAVE${FLAG_})
-        if (HAVE${FLAG_})
+        check_if_cxx_compiler_flag_supported(${FLAG_} FLAG_SUPPORTED)
+        if (FLAG_SUPPORTED)
             foreach(SRC_ IN LISTS append_options_FILES)
-                get_source_file_property(SRC_PROPS_${SRC_} ${SRC_} COMPILE_OPTIONS)
-                if ("${SRC_PROPS_${SRC_}}" STREQUAL "NOTFOUND" OR "${SRC_PROPS_${SRC_}}" STREQUAL "")
+                get_source_file_property(OLD_OPTS ${SRC_} COMPILE_OPTIONS)
+                if (NOT OLD_OPTS)
                     set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${FLAG_}")
-                elseif(NOT "${FLAG_}" IN_LIST SRC_PROPS_${SRC_})
-                    set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${SRC_PROPS_${SRC_}};${FLAG_}")
+                elseif(NOT "${FLAG_}" IN_LIST OLD_OPTS)
+                    set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${OLD_OPTS};${FLAG_}")
                 endif()
             endforeach()
         endif()

From ff727ad488ca652d903b867f54725c949e4a2c93 Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Wed, 5 Apr 2023 20:46:55 -0400
Subject: [PATCH 09/11] Added status back to append compile options for debug

---
 CMakeLists.txt | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 25d4016d5c1..90e11d8342a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -81,8 +81,10 @@ function(append_source_file_compile_options)
                 get_source_file_property(OLD_OPTS ${SRC_} COMPILE_OPTIONS)
                 if (NOT OLD_OPTS)
                     set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${FLAG_}")
+                    message(STATUS "Adding '${FLAG_}' for '${SRC_}' - options: ${OLD_OPTS}")
                 elseif(NOT "${FLAG_}" IN_LIST OLD_OPTS)
                     set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${OLD_OPTS};${FLAG_}")
+                    message(STATUS "Appending '${FLAG_}' for '${SRC_}' - options: ${OLD_OPTS}")
                 endif()
             endforeach()
         endif()

From fab83751e3e835dd19779c098efb61775165c7eb Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Wed, 5 Apr 2023 21:24:16 -0400
Subject: [PATCH 10/11] check compile flag variable is global

---
 CMakeLists.txt | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 90e11d8342a..c86fa4869ed 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,5 @@
 cmake_minimum_required(VERSION 3.15)
+message(STATUS "CMake version: ${CMAKE_VERSION}")
 
 set(CMAKE_BUILD_TYPE Debug CACHE STRING "")
 project(RealmCore)
@@ -61,7 +62,6 @@ function(add_cxx_flag_if_supported flag)
     endif()
 endfunction()
 
-
 # Usage: append_source_file_compile_options(FILES <file1>[ <file2>...] FLAGS <flag1>[ <flag2>...])
 function(append_source_file_compile_options)
     set(options)
@@ -75,8 +75,9 @@ function(append_source_file_compile_options)
         message(FATAL_ERROR "Missing FLAGS argument for append_source_file_compile_options")
     endif()
     foreach(FLAG_ IN LISTS append_options_FLAGS)
-        check_if_cxx_compiler_flag_supported(${FLAG_} FLAG_SUPPORTED)
-        if (FLAG_SUPPORTED)
+        message(STATUS "Append compile flag: ${FLAG_}")
+        check_if_cxx_compiler_flag_supported(${FLAG_} HAVE${FLAG_})
+        if (HAVE${FLAG_})
             foreach(SRC_ IN LISTS append_options_FILES)
                 get_source_file_property(OLD_OPTS ${SRC_} COMPILE_OPTIONS)
                 if (NOT OLD_OPTS)

From c404a42c36b69186c303c3e00e9f4f1449e2a273 Mon Sep 17 00:00:00 2001
From: Michael Wilkerson-Barker <michael.wilkersonbarker@mongodb.com>
Date: Wed, 5 Apr 2023 21:49:02 -0400
Subject: [PATCH 11/11] Cleanup after debugging

---
 CMakeLists.txt | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c86fa4869ed..e1895b8f32b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -44,6 +44,8 @@ elseif(APPLE)
     set(CMAKE_VISIBILITY_INLINES_HIDDEN 1)
 endif()
 
+# Sets/clears the {FLAG} variable if the compiler flag is supported or not
+# The compiler flag check is only performed once and the value is cached as the out variable name
 function(check_if_cxx_compiler_flag_supported flag out_var)
     if(flag MATCHES "^-Wno-")
         # Compilers ignore unknown -Wno-foo flags, so look for -Wfoo instead.
@@ -75,17 +77,14 @@ function(append_source_file_compile_options)
         message(FATAL_ERROR "Missing FLAGS argument for append_source_file_compile_options")
     endif()
     foreach(FLAG_ IN LISTS append_options_FLAGS)
-        message(STATUS "Append compile flag: ${FLAG_}")
         check_if_cxx_compiler_flag_supported(${FLAG_} HAVE${FLAG_})
         if (HAVE${FLAG_})
             foreach(SRC_ IN LISTS append_options_FILES)
                 get_source_file_property(OLD_OPTS ${SRC_} COMPILE_OPTIONS)
                 if (NOT OLD_OPTS)
                     set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${FLAG_}")
-                    message(STATUS "Adding '${FLAG_}' for '${SRC_}' - options: ${OLD_OPTS}")
                 elseif(NOT "${FLAG_}" IN_LIST OLD_OPTS)
                     set_source_files_properties(${SRC_} PROPERTIES COMPILE_OPTIONS "${OLD_OPTS};${FLAG_}")
-                    message(STATUS "Appending '${FLAG_}' for '${SRC_}' - options: ${OLD_OPTS}")
                 endif()
             endforeach()
         endif()