From f9466c40f84ca1947ffa8a7d9190fcb043440ac4 Mon Sep 17 00:00:00 2001
From: Mischa Spiegelmock <revmischa@cpan.org>
Date: Sat, 31 Oct 2015 21:54:34 -0700
Subject: [PATCH 1/3] stick OSX install in /usr/local prefix; 10.11 does not
 allow writing to /usr/{include,lib}

---
 config/Makefile.darwin | 1 +
 1 file changed, 1 insertion(+)

diff --git a/config/Makefile.darwin b/config/Makefile.darwin
index 8dd6262..8daa371 100644
--- a/config/Makefile.darwin
+++ b/config/Makefile.darwin
@@ -1,3 +1,4 @@
+GLEW_DEST=/usr/local
 NAME = $(GLEW_NAME)
 CC = cc
 LD = cc

From c8c0c1e480d2e236342345a6a93c1f20f8996531 Mon Sep 17 00:00:00 2001
From: Nigel Stewart <nigels@users.sourceforge.net>
Date: Tue, 17 Nov 2015 21:23:51 +1000
Subject: [PATCH 2/3] OSX install to /usr/local as required by 10.11 El Capitan

---
 config/Makefile.darwin           | 2 +-
 config/Makefile.darwin-ppc       | 1 +
 config/Makefile.darwin-universal | 1 +
 config/Makefile.darwin-x86_64    | 1 +
 4 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/config/Makefile.darwin b/config/Makefile.darwin
index 8daa371..93b2052 100644
--- a/config/Makefile.darwin
+++ b/config/Makefile.darwin
@@ -1,4 +1,4 @@
-GLEW_DEST=/usr/local
+GLEW_DEST = /usr/local
 NAME = $(GLEW_NAME)
 CC = cc
 LD = cc
diff --git a/config/Makefile.darwin-ppc b/config/Makefile.darwin-ppc
index 60ae3fd..7dd99ff 100644
--- a/config/Makefile.darwin-ppc
+++ b/config/Makefile.darwin-ppc
@@ -1,3 +1,4 @@
+GLEW_DEST = /usr/local
 NAME = $(GLEW_NAME)
 CC = cc
 LD = cc
diff --git a/config/Makefile.darwin-universal b/config/Makefile.darwin-universal
index 2b3156b..dfd4eef 100644
--- a/config/Makefile.darwin-universal
+++ b/config/Makefile.darwin-universal
@@ -1,3 +1,4 @@
+GLEW_DEST = /usr/local
 NAME = $(GLEW_NAME)
 CC = cc
 LD = cc
diff --git a/config/Makefile.darwin-x86_64 b/config/Makefile.darwin-x86_64
index 5e8156b..437bad4 100644
--- a/config/Makefile.darwin-x86_64
+++ b/config/Makefile.darwin-x86_64
@@ -1,3 +1,4 @@
+GLEW_DEST = /usr/local
 NAME = $(GLEW_NAME)
 CC = cc
 LD = cc

From 66c5229ec2ece475704fa0fd162c0dae545842e9 Mon Sep 17 00:00:00 2001
From: Tamas Kenez <tamas.kenez@adasworks.com>
Date: Tue, 10 Nov 2015 11:53:16 +0100
Subject: [PATCH 3/3] cmake: allow calling find_package(GLEW) multiple times

---
 build/cmake/glew-config.cmake        | 20 +++++++++++++++++---
 build/cmake/testbuild/CMakeLists.txt |  1 +
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/build/cmake/glew-config.cmake b/build/cmake/glew-config.cmake
index 8d2907a..29efcbe 100644
--- a/build/cmake/glew-config.cmake
+++ b/build/cmake/glew-config.cmake
@@ -40,7 +40,21 @@ endif()
 foreach(_glew_target glew glewmx)
   set(_glew_src_target "GLEW::${_glew_target}${_glew_target_postfix}")
   string(TOUPPER "GLEW::${_glew_target}" _glew_dest_target)
-  add_library(${_glew_dest_target} ${_glew_target_type} IMPORTED)
-  # message(STATUS "add_library(${_glew_dest_target} ${_glew_target_type} IMPORTED)")
-  copy_imported_target_properties(${_glew_src_target} ${_glew_dest_target})
+  if(TARGET ${_glew_dest_target})
+    get_target_property(_glew_previous_src_target ${_glew_dest_target}
+      _GLEW_SRC_TARGET)
+    if(NOT _glew_previous_src_target STREQUAL _glew_src_target)
+      message(FATAL_ERROR "find_package(GLEW) was called the second time with "
+        "different GLEW_USE_STATIC_LIBS setting. Previously, "
+        "`glew-config.cmake` created ${_glew_dest_target} as a copy of "
+        "${_glew_previous_src_target}. Now it attempted to copy it from "
+        "${_glew_src_target}. ")
+    endif()
+  else()
+    add_library(${_glew_dest_target} ${_glew_target_type} IMPORTED)
+    # message(STATUS "add_library(${_glew_dest_target} ${_glew_target_type} IMPORTED)")
+    copy_imported_target_properties(${_glew_src_target} ${_glew_dest_target})
+    set_target_properties(${_glew_dest_target} PROPERTIES
+      _GLEW_SRC_TARGET ${_glew_src_target})
+  endif()
 endforeach()
diff --git a/build/cmake/testbuild/CMakeLists.txt b/build/cmake/testbuild/CMakeLists.txt
index 275e24d..27bcf2d 100644
--- a/build/cmake/testbuild/CMakeLists.txt
+++ b/build/cmake/testbuild/CMakeLists.txt
@@ -2,6 +2,7 @@ cmake_minimum_required(VERSION 2.8.12)
 project(glew-cmake-test)
 
 find_package(GLEW REQUIRED CONFIG)
+find_package(GLEW REQUIRED CONFIG) # call twice to test multiple call
 find_package(OpenGL REQUIRED)
 
 add_executable(cmake-test main.c)