From d0484a9ea9331f2cedb080f06944d737343414f1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9o=20Lam?= <leo@leolam.fr>
Date: Sun, 25 Apr 2021 19:41:07 +0200
Subject: [PATCH] CMake: Fix MSVC flags for Release/RelWithDebInfo

See https://gitlab.kitware.com/cmake/cmake/-/issues/20812

Manually redefine MSVC flags to match Visual Studio defaults
and ensure that Release builds generate debug info.
---
 CMake/FlagsOverride.cmake | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/CMake/FlagsOverride.cmake b/CMake/FlagsOverride.cmake
index 39c55aa62a..d52cf4b153 100644
--- a/CMake/FlagsOverride.cmake
+++ b/CMake/FlagsOverride.cmake
@@ -1,7 +1,11 @@
 if(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
-  foreach(f CMAKE_C_FLAGS_DEBUG CMAKE_CXX_FLAGS_DEBUG CMAKE_C_FLAGS_RELWITHDEBINFO CMAKE_CXX_FLAGS_RELWITHDEBINFO)
-	  if("${${f}}" MATCHES "/Zi")
-		  string(REGEX REPLACE "/Zi" "/Z7" "${f}" "${${f}}")
-		endif()
-	endforeach()
-endif()
\ No newline at end of file
+  # The default MSVC flags for Release and RelWithDebInfo are poorly chosen
+  # (see issue https://gitlab.kitware.com/cmake/cmake/-/issues/20812)
+  # By default, inlining is disabled for RelWithDebInfo.
+  # Manually redefine MSVC flags to match Visual Studio defaults
+  # and ensure that Release builds generate debug info.
+  foreach(f CMAKE_C_FLAGS_RELWITHDEBINFO CMAKE_C_FLAGS_RELEASE CMAKE_CXX_FLAGS_RELWITHDEBINFO CMAKE_CXX_FLAGS_RELEASE)
+    # optimize, define NDEBUG, generate debug info
+    set(${f} "/O2 /DNDEBUG /Z7")
+  endforeach()
+endif()