From a2df9179747bf8b90eca892fa323e17ab973739e Mon Sep 17 00:00:00 2001
From: "D.R.racer" <drracer@drracer.eu>
Date: Sat, 18 Jun 2022 01:33:25 +0200
Subject: [PATCH] Enable LTO

shaves off ~10% of the code size which is very nice ... also some RAM, but we are not short on RAM in this case.
---
 CMakeLists.txt | 1 +
 src/main.cpp   | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8aca20e..c18db27 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -143,6 +143,7 @@ if(CMAKE_CROSSCOMPILING)
   #]]
 
   # limit the text section to 28K (32K - 4k reserved for the bootloader)
+  set_target_properties(firmware PROPERTIES INTERPROCEDURAL_OPTIMIZATION True)
   target_link_options(firmware PUBLIC -Wl,--defsym=__TEXT_REGION_LENGTH__=28K)
 
   # generate firmware.bin file
diff --git a/src/main.cpp b/src/main.cpp
index b37af1b..44a4f75 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -166,3 +166,9 @@ int main() {
     }
     return 0;
 }
+
+// make lto happy...
+extern "C" void __cxa_pure_virtual() {
+    while (1)
+        ;
+}