diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2ffe6d3f26..2bf99209c5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -141,15 +141,18 @@ list(GET _version_list 4 LYX_RELEASE_PATCH)
 if(LYX_BUILD_TYPE STREQUAL "development")
   set(DefaultLyxDebug ON)
   set(DefaultLyxRelease OFF)
-  set(DefaultStdlibDebug ON)
+  set(DefaultLyxStdlibDebug ON)
+  set(DefaultLyxEnableAssertions ON)
 elseif(LYX_BUILD_TYPE STREQUAL "prerelease")
   set(DefaultLyxDebug OFF)
   set(DefaultLyxRelease OFF)
-  set(DefaultStdlibDebug OFF)
+  set(DefaultLyxStdlibDebug OFF)
+  set(DefaultLyxEnableAssertions OFF)
 elseif(LYX_BUILD_TYPE STREQUAL "release")
   set(DefaultLyxDebug OFF)
   set(DefaultLyxRelease ON)
-  set(DefaultStdlibDebug OFF)
+  set(DefaultLyxStdlibDebug OFF)
+  set(DefaultLyxEnableAssertions OFF)
 else()
   message(FATAL_ERROR "Unknown build type (${LYX_BUILD_TYPE}) encountered")
 endif()
@@ -173,6 +176,7 @@ LYX_OPTION(HUNSPELL         "Require Hunspell" OFF ALL)
 LYX_OPTION(RELEASE          "Build release version, build debug when disabled" ${DefaultLyxRelease} ALL)
 LYX_OPTION(DEBUG            "Enforce debug build"  ${DefaultLyxDebug} ALL)
 LYX_OPTION(NO_OPTIMIZE      "Don't use any optimization/debug flags"  OFF ALL)
+LYX_OPTION(ENABLE_ASSERTIONS "Run sanity checks in the program"  ${DefaultLyxEnableAssertions} ALL)
 LYX_OPTION(PACKAGE_SUFFIX   "Use version suffix for packaging" ON ALL)
 LYX_STRING(SUFFIX_VALUE     "Use this string as suffix" "")
 LYX_OPTION(PCH              "Use precompiled headers" OFF ALL)
@@ -209,7 +213,7 @@ LYX_OPTION(EXTERNAL_BOOST       "Use external boost" OFF GCC)
 LYX_OPTION(PROGRAM_SUFFIX       "Append version suffix to binaries" ON GCC)
 LYX_OPTION(DEBUG_GLIBC          "Enable libstdc++ debug mode" OFF GCC)
 LYX_OPTION(DEBUG_GLIBC_PEDANTIC "Enable libstdc++ pedantic debug mode" OFF GCC)
-LYX_OPTION(STDLIB_DEBUG         "Use debug stdlib" ${DefaultStdlibDebug} GCC)
+LYX_OPTION(STDLIB_DEBUG         "Use debug stdlib" ${DefaultLyxStdlibDebug} GCC)
 
 # MSVC specific
 LYX_OPTION(CONSOLE               "Show console on Windows" ON MSVC)
@@ -644,17 +648,24 @@ else()
 	set(library_type STATIC)
 endif()
 
+if(LYX_ENABLE_ASSERTIONS)
+  set(LYX_CXX_FLAGS " -DENABLE_ASSERTIONS=1")
+else()
+  set(LYX_CXX_FLAGS "")
+endif()
+
 if(MSVC)
   if (CXX11_FLAG MATCHES "\\+\\+([0-9]+)")
     set(CMAKE_CXX_STANDARD ${CMAKE_MATCH_1})
     message(STATUS "CMAKE_CXX_STANDARD set to ${CMAKE_CXX_STANDARD}")
   endif()
+  set(CMAKE_CXX_FLAGS       "${CMAKE_CXX_FLAGS}${LYX_CXX_FLAGS}")
 else()
 	if(NOT LYX_QUIET)
 		set(CMAKE_VERBOSE_MAKEFILE ON)
 	endif()
-	set(LYX_CXX_FLAGS "-Wall -Wunused-parameter ${LYX_GCC11_MODE}")
-	if(LYX_CXX_FLAGS MATCHES "\\+\\+(14|11|98)")
+	set(LYX_CXX_FLAGS "-Wall -Wunused-parameter ${LYX_GCC11_MODE}${LYX_CXX_FLAGS}")
+	if(LYX_GCC11_MODE MATCHES "\\+\\+(14|11|98)")
 	  # Thanks to Brad King <brad.king@kitware.com>
 	  # for the pointer to https://cmake.org/cmake/help/v3.6/variable/CMAKE_CXX_STANDARD.html
 	  # This allows us to use QT5.7 with recent g++ (version >= 4.9) compilers