From c5ebd7c88e4654f149ea2eabf480d5154659d0ee Mon Sep 17 00:00:00 2001
From: Maxime Gimeno <maxime.gimeno@gmail.com>
Date: Fri, 2 Apr 2021 14:30:02 +0200
Subject: [PATCH] dichotomize multiconfig generators

---
 Installation/cmake/modules/FindGMP.cmake | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/Installation/cmake/modules/FindGMP.cmake b/Installation/cmake/modules/FindGMP.cmake
index b10f245fd27..3f94b30ae9f 100644
--- a/Installation/cmake/modules/FindGMP.cmake
+++ b/Installation/cmake/modules/FindGMP.cmake
@@ -38,16 +38,28 @@ if( NOT GMP_in_cache )
     PATH_SUFFIXES lib
     DOC "Path to the Release GMP library"
     )
-	
-	find_library(GMP_LIBRARY_DEBUG NAMES gmpd libgmp-10 mpir
+
+  find_library(GMP_LIBRARY_DEBUG NAMES gmpd libgmp-10 mpir
     HINTS ENV GMP_LIB_DIR
           ENV GMP_DIR
           ${CGAL_INSTALLATION_PACKAGE_DIR}/auxiliary/gmp/lib
     PATH_SUFFIXES lib
     DOC "Path to the Debug GMP library"
     )
-	
-	set(GMP_LIBRARIES $<IF:$<CONFIG:Debug>,${GMP_LIBRARY_DEBUG},${GMP_LIBRARY_RELEASE}>)
+
+  if(NOT GMP_LIBRARY_DEBUG)
+    set(GMP_LIBRARY_DEBUG ${GMP_LIBRARY_RELEASE})
+  endif()
+  get_property(IS_MULTI_CONFIG GLOBAL PROPERTY GENERATOR_IS_MULTI_CONFIG)
+  if(IS_MULTI_CONFIG)
+  set(GMP_LIBRARIES $<IF:$<CONFIG:Debug>,${GMP_LIBRARY_DEBUG},${GMP_LIBRARY_RELEASE}>)
+else()
+  if("${CMAKE_BUILD_TYPE}" STREQUAL "Debug")
+    set(GMP_LIBRARIES ${GMP_LIBRARY_DEBUG})
+  else()
+    set(GMP_LIBRARIES ${GMP_LIBRARY_RELEASE})
+  endif()
+endif()
    if ( GMP_LIBRARIES )
     get_filename_component(GMP_LIBRARIES_DIR ${GMP_LIBRARIES} PATH CACHE )
   endif()