From: Jakub Jirutka <jakub@jirutka.cz>
Date: Mon, 11 Apr 2017 3:23:00 +0200
Subject: [PATCH] Build both static and dynamic library

This is very hack-ish, it makes option BUILD_SHARED_LIBS unusable.
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -28,7 +28,6 @@
 # Build options
 #
 OPTION( SONAME				"Set the (SO)VERSION of the target"		ON  )
-OPTION( BUILD_SHARED_LIBS	"Build Shared Library (OFF for Static)"	ON  )
 OPTION( THREADSAFE			"Build libgit2 as threadsafe"			ON )
 OPTION( BUILD_CLAR			"Build Tests using the Clar suite"		ON  )
 OPTION( BUILD_EXAMPLES		"Build library usage example apps"		OFF )
@@ -45,6 +44,8 @@
 OPTION( CURL			"Use curl for HTTP if available" ON)
 OPTION( DEBUG_POOL			"Enable debug pool allocator"			OFF )
 
+SET( BUILD_SHARED_LIBS ON )
+
 IF(DEBUG_POOL)
 	ADD_DEFINITIONS(-DGIT_DEBUG_POOL)
 ENDIF()
@@ -609,7 +610,8 @@
 ENDIF()
 
 # Compile and link libgit2
-ADD_LIBRARY(git2 ${SRC_H} ${SRC_GIT2} ${SRC_OS} ${SRC_ZLIB} ${SRC_HTTP} ${SRC_REGEX} ${SRC_SSH} ${SRC_SHA1} ${WIN_RC})
+ADD_LIBRARY(objlib OBJECT ${SRC_H} ${SRC_GIT2} ${SRC_OS} ${SRC_ZLIB} ${SRC_HTTP} ${SRC_REGEX} ${SRC_SSH} ${SRC_SHA1} ${WIN_RC})
+ADD_LIBRARY(git2 SHARED $<TARGET_OBJECTS:objlib>)
 TARGET_LINK_LIBRARIES(git2 ${SECURITY_DIRS})
 TARGET_LINK_LIBRARIES(git2 ${COREFOUNDATION_DIRS})
 TARGET_LINK_LIBRARIES(git2 ${SSL_LIBRARIES})
@@ -618,6 +620,9 @@
 TARGET_LINK_LIBRARIES(git2 ${ICONV_LIBRARIES})
 TARGET_OS_LIBRARIES(git2)
 
+ADD_LIBRARY(git2_static STATIC $<TARGET_OBJECTS:objlib>)
+SET_TARGET_PROPERTIES(git2_static PROPERTIES OUTPUT_NAME git2 CLEAN_DIRECT_OUTPUT 1)
+
 # Workaround for Cmake bug #0011240 (see http://public.kitware.com/Bug/view.php?id=11240)
 # Win64+MSVC+static libs = linker error
 IF(MSVC AND GIT_ARCH_64 AND NOT BUILD_SHARED_LIBS)
@@ -646,7 +651,7 @@
 ENDIF ()
 
 # Install
-INSTALL(TARGETS git2
+INSTALL(TARGETS git2 git2_static
 	RUNTIME DESTINATION ${BIN_INSTALL_DIR}
 	LIBRARY DESTINATION ${LIB_INSTALL_DIR}
 	ARCHIVE DESTINATION ${LIB_INSTALL_DIR}