From 73f4fc1cd9970a04b5b123d8c3001e3f938a4898 Mon Sep 17 00:00:00 2001
From: Juan Cruz Viotti <jv@jviotti.com>
Date: Fri, 12 Jul 2024 10:00:29 +0100
Subject: [PATCH] Make use of link time optimisation  (#121)

Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>
---
 DEPENDENCIES                        |  2 +-
 vendor/noa/cmake/noa/defaults.cmake | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/DEPENDENCIES b/DEPENDENCIES
index d162f3e6..3914a117 100644
--- a/DEPENDENCIES
+++ b/DEPENDENCIES
@@ -1,4 +1,4 @@
 vendorpull https://github.com/sourcemeta/vendorpull dea311b5bfb53b6926a4140267959ae334d3ecf4
-noa https://github.com/sourcemeta/noa 2bc3138b80e575786bec418c91fc2058c6836993
+noa https://github.com/sourcemeta/noa 7e26abce7a4e31e86a16ef2851702a56773ca527
 jsontoolkit https://github.com/sourcemeta/jsontoolkit 0ee1179c37f989ca06a44f73e1aa3e7d71674f15
 hydra https://github.com/sourcemeta/hydra 3c53d3fdef79e9ba603d48470a508cc45472a0dc
diff --git a/vendor/noa/cmake/noa/defaults.cmake b/vendor/noa/cmake/noa/defaults.cmake
index 21a50b3c..0709ee22 100644
--- a/vendor/noa/cmake/noa/defaults.cmake
+++ b/vendor/noa/cmake/noa/defaults.cmake
@@ -69,3 +69,26 @@ if(WIN32)
   # For DLL files
   set(CMAKE_LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/bin" CACHE STRING "")
 endif()
+
+# Enable IPO/LTO to help the compiler optimize across modules.
+# Only do so in release, given these optimizations can significantly
+# increase build times.
+# See: https://cmake.org/cmake/help/latest/module/CheckIPOSupported.html
+if(CMAKE_BUILD_TYPE STREQUAL "Release" AND NOT BUILD_SHARED_LIBS)
+  include(CheckIPOSupported)
+  check_ipo_supported(RESULT ipo_supported OUTPUT ipo_supported_error)
+  if(ipo_supported)
+    # TODO: Make IPO/LTO work on Linux + LLVM
+    if(APPLE OR NOT NOA_COMPILER_LLVM)
+      message(STATUS "Enabling IPO")
+      cmake_policy(SET CMP0069 NEW)
+      set(CMAKE_INTERPROCEDURAL_OPTIMIZATION ON)
+    else()
+      message(WARNING "Avoiding IPO on this configuration")
+    endif()
+  else()
+    message(WARNING "IPO not supported: ${ipo_supported_error}")
+  endif()
+  unset(ipo_supported)
+  unset(ipo_supported_error)
+endif()