fix for ZENOHC_CARGO_FLAGS passing

CMakeLists.txt

@@ -170,7 +170,15 @@ set_genexpr_condition(libs DEBUG $<CONFIG:Debug> "${libsd}" "${libsr}")
 # Build rust sources
 #
 set_genexpr_condition(cargo_release_flag DEBUG $<CONFIG:Debug> "" "--release")
-set(cargo_flags ${ZENOHC_CARGO_FLAGS} ${cargo_release_flag})
+# cargo_flags is a list of command line arguments for cargo. It should be represented as a list in CMake, 
+# i.e. if ZENOHC_CARGO_FLAGS constains space, it shoudl be replaced to list separator ";". This is important for further "add_custom_command" call
+# where each list element is passed as separate argument to system exec call.
+# This makes impossible to use ";" in ZENOHC_CARGO_FLAGS, let's hope it's not a problem for now.
+if (ZENOHC_CARGO_FLAGS MATCHES ";")
+	message(FATAL_ERROR "ZENOHC_CARGO_FLAGS contains ';' which is not allowed (see comment in CMakeLists.txt))")
+endif()
+string(REPLACE " " ";" cargo_flags "${ZENOHC_CARGO_FLAGS}")
+set(cargo_flags ${cargo_flags} ${cargo_release_flag})
 set(cargo_flags ${cargo_flags} --manifest-path=${cargo_toml_dir}/Cargo.toml)
 
 if(ZENOHC_BUILD_WITH_LOGGER_AUTOINIT)
@@ -192,6 +200,7 @@ add_custom_command(
 	COMMAND ${CMAKE_COMMAND} -E echo \"RUSTFLAGS = $$RUSTFLAGS\"
 	COMMAND ${CMAKE_COMMAND} -E echo \"cargo +${ZENOHC_CARGO_CHANNEL} build ${cargo_flags}\"
 	COMMAND cargo +${ZENOHC_CARGO_CHANNEL} build ${cargo_flags}
+	VERBATIM
 )
 add_custom_target(cargo ALL DEPENDS "${libs}")