Merge pull request #643 from gaoxifeng/master

fixed GMP of libigl.cmake for linux

Former-commit-id: d4b67260855fe901541f2949ff21819147c08a4d

shared/cmake/libigl.cmake

@@ -140,8 +140,8 @@ if(LIBIGL_WITH_CGAL)
     compile_igl_module("cgal" "copyleft/")
     if(WIN32)
       set(Boost_USE_STATIC_LIBS ON) # Favor static Boost libs on Windows
-      target_include_directories(igl_cgal ${IGL_SCOPE} "${GMP_INCLUDE_DIR}" "${MPFR_INCLUDE_DIR}")
     endif()
+    target_include_directories(igl_cgal ${IGL_SCOPE} "${GMP_INCLUDE_DIR}" "${MPFR_INCLUDE_DIR}")
     find_package(Boost 1.48 REQUIRED thread system)
     target_include_directories(igl_cgal ${IGL_SCOPE} ${CGAL_INCLUDE_DIRS} ${Boost_INCLUDE_DIRS})
     target_link_libraries(igl_cgal ${IGL_SCOPE} CGAL::CGAL CGAL::CGAL_Core ${Boost_LIBRARIES})