ports/rp2: Use nano.specs for C++ modules.

Gadgetoid · Gadgetoid · commit 043bca8661d4 · 2023-03-28T14:43:27.000+01:00
Remove C++ stack unwinding and exception handling in all cases. Set options as per https://github.com/raspberrypi/pico-sdk/blob/master/src/rp2_common/pico_cxx_options/CMakeLists.txt Save around 10,880 bytes of RAM. Signed-off-by: Phil Howard <phil@gadgetoid.com>
diff --git a/ports/rp2/CMakeLists.txt b/ports/rp2/CMakeLists.txt
@@ -365,6 +365,16 @@ target_compile_options(${MICROPY_TARGET} PRIVATE
     -Werror
 )
 
+# Do not include stack unwinding & exception handling for C++ user modules
+target_compile_definitions(usermod INTERFACE PICO_CXX_ENABLE_EXCEPTIONS=0)
+target_compile_options(usermod INTERFACE $<$<COMPILE_LANGUAGE:CXX>:
+    -fno-exceptions
+    -fno-unwind-tables
+    -fno-rtti
+    -fno-use-cxa-atexit
+>)
+target_link_options(usermod INTERFACE -specs=nano.specs)
+
 set_source_files_properties(
     ${PICO_SDK_PATH}/src/rp2_common/pico_double/double_math.c
     ${PICO_SDK_PATH}/src/rp2_common/pico_float/float_math.c
