Hello, Sergey

<snipped>

--- a/test/tarantool-tests/lj-551-bytecode-c-broken-macro/CMakeLists.txt
+++ b/test/tarantool-tests/lj-551-bytecode-c-broken-macro/CMakeLists.txt
@@ -1,5 +1,6 @@
  set(LIB_NAME "bcsaved_clib")
-set(LUA_FILE ${CMAKE_CURRENT_SOURCE_DIR}/${LIB_NAME}.lua)
+set(LUA_FILE_ORIG ${CMAKE_CURRENT_SOURCE_DIR}/bcsaved.lua)
+set(LUA_FILE ${CMAKE_CURRENT_BINARY_DIR}/${LIB_NAME}.lua)
  set(C_FILE ${LIB_NAME}.c)

  make_lua_path(LUA_PATH
@@ -8,11 +9,24 @@ make_lua_path(LUA_PATH
      ${PROJECT_SOURCE_DIR}/src/jit/?.lua
  )

+add_custom_target(copy_lua
+  COMMAND ${CMAKE_COMMAND} -E
+    copy
+      ${LUA_FILE_ORIG}
+      ${LUA_FILE}
+  DEPENDS ${LUA_FILE_ORIG}
+  BYPRODUCTS ${LUA_FILE}
+  COMMENT "Copying Lua module"
+  VERBATIM
+)
+
  add_custom_target(export_bc
    COMMAND ${CMAKE_COMMAND} -E
      env
        LUA_PATH=${LUA_PATH}
      ${LUAJIT_BINARY} -b ${LUA_FILE} ${C_FILE}
+  COMMAND ${CMAKE_COMMAND} -E
+    remove ${LUA_FILE}
    DEPENDS luajit-main ${LUA_FILE}
    BYPRODUCTS ${C_FILE}
    COMMENT "Exporting bytecode to a C file"

The test still doesn't fail before the commit.
The reason is that the C file is compiled by C compiler, not the C++
compiler (so this macro is irrelevant).

I suppose that we should add a .cpp file for the test too (and add the
LINKER_LANGUAGE CXX [1] property for this target if its necessary).

Unfortunately, setting property with LINKER_LANGUAGE is not enough.

Additionally one need setting CXX language for a project or enable CXX in required CMakeLists.txt

and it is better to have .cc extension for a file too. Otherwise CMake fails to build a file by CXX compiler.

I believe you will not against to backporting e826d0c101d750fac8334d71e221c50d8dbe236c ("Add 'cc' file type for saving bytecode.")

as well because commit enables saving bc to .cc file directly.

Final patch:

diff --git a/test/tarantool-tests/lj-551-bytecode-c-broken-macro/CMakeLists.txt b/test/tarantool-tests/lj-551-bytecode-c-broken-macro/CMakeLists.txt
index 45857386..1baf6ec8 100644
--- a/test/tarantool-tests/lj-551-bytecode-c-broken-macro/CMakeLists.txt
+++ b/test/tarantool-tests/lj-551-bytecode-c-broken-macro/CMakeLists.txt
@@ -1,7 +1,9 @@
+enable_language(CXX)
+
 set(LIB_NAME "bcsaved_clib")
 set(LUA_FILE_ORIG ${CMAKE_CURRENT_SOURCE_DIR}/bcsaved.lua)
 set(LUA_FILE ${CMAKE_CURRENT_BINARY_DIR}/${LIB_NAME}.lua)
-set(C_FILE ${LIB_NAME}.c)
+set(CXX_FILE ${LIB_NAME}.cc)
 
 make_lua_path(LUA_PATH
   PATHS
@@ -24,14 +26,14 @@ add_custom_target(export_bc
   COMMAND ${CMAKE_COMMAND} -E
     env
       LUA_PATH=${LUA_PATH}
-    ${LUAJIT_BINARY} -b ${LUA_FILE} ${C_FILE}
+    ${LUAJIT_BINARY} -b ${LUA_FILE} ${CXX_FILE}
   COMMAND ${CMAKE_COMMAND} -E
     remove ${LUA_FILE}
   DEPENDS luajit-main ${LUA_FILE}
-  BYPRODUCTS ${C_FILE}
+  BYPRODUCTS ${CXX_FILE}

 -  COMMENT "Exporting bytecode to a C file"
 + COMMENT "Exporting bytecode to a CXX file"
   VERBATIM
 )
 
-BuildTestCLib(${LIB_NAME} ${C_FILE})
+BuildTestCLib(${LIB_NAME} ${CXX_FILE})
 add_dependencies(${LIB_NAME} export_bc)

[1]: https://cmake.org/cmake/help/latest/prop_tgt/LINKER_LANGUAGE.html#linker-language