From 30ce32a67d9a2008da6610e4b7739e94b233d0d8 Mon Sep 17 00:00:00 2001
From: Kefu Chai <kchai@redhat.com>
Date: Sun, 10 Apr 2016 22:37:59 +0800
Subject: [PATCH] cmake: pass RULE_LAUNCHER_* to cython

* pass the environment variables using `env` to pass environment
  varibles with space(s) in them to the COMMAND in add_custom_target.
  otherwise, cmake will try to quote the space with "\". this breaks the
  generated command line.
* add a comment for ccache to note that we do not expect ccache to speed
  up linking. we use it as the linker's launcher to workaround
  https://bugs.python.org/issue8027. to be specific,
  distutils.UnixCCompiler.link overwrites the first linker CLI's arg
  using the the first C++ compiler's CLI arg, if "env" is not used to
  launch the linker. this breaks the cythonization of our pybind APIs.

Signed-off-by: Kefu Chai <kchai@redhat.com>
---
 CMakeLists.txt                   | 3 +++
 src/pybind/CMakeLists.txt        | 5 +++++
 src/pybind/cephfs/CMakeLists.txt | 4 ++++
 src/pybind/rados/CMakeLists.txt  | 4 ++++
 src/pybind/rbd/CMakeLists.txt    | 4 ++++
 5 files changed, 20 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3391b4294b5..b36b682734a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,6 +25,9 @@ if(WITH_CCACHE)
   if(CCACHE_FOUND)
     message(STATUS "Building with ccache: ${CCACHE_FOUND}, CCACHE_DIR=$ENV{CCACHE_DIR}")
     set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ccache)
+    # ccache does not accelerate link (ld), but let it handle it. by passing it
+    # along with cc to python's distutils, we are able to workaround
+    # https://bugs.python.org/issue8027.
     set_property(GLOBAL PROPERTY RULE_LAUNCH_LINK ccache)
   else(CCACHE_FOUND)
     message(FATAL_ERROR "Can't find ccache. Is it installed?")
diff --git a/src/pybind/CMakeLists.txt b/src/pybind/CMakeLists.txt
index 5fbbc7f6518..6a4ba94ebd0 100644
--- a/src/pybind/CMakeLists.txt
+++ b/src/pybind/CMakeLists.txt
@@ -1,4 +1,9 @@
 set(CYTHON_MODULE_DIR ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/cython_modules)
+get_property(compiler_launcher GLOBAL PROPERTY RULE_LAUNCH_COMPILE)
+get_property(link_launcher GLOBAL PROPERTY RULE_LAUNCH_LINK)
+set(PY_CC \"${compiler_launcher} ${CMAKE_C_COMPILER}\")
+set(PY_CXX \"${compiler_launcher} ${CMAKE_CXX_COMPILER}\")
+set(PY_LDSHARED \"${link_launcher} ${CMAKE_C_COMPILER} -shared\")
 
 add_subdirectory(rados)
 add_subdirectory(rbd)
diff --git a/src/pybind/cephfs/CMakeLists.txt b/src/pybind/cephfs/CMakeLists.txt
index 91d36ceaa9d..b3f4cf44dc3 100644
--- a/src/pybind/cephfs/CMakeLists.txt
+++ b/src/pybind/cephfs/CMakeLists.txt
@@ -1,5 +1,9 @@
 add_custom_target(cython_cephfs
   COMMAND
+  env
+  CC=${PY_CC}
+  CXX=${PY_CXX}
+  LDSHARED=${PY_LDSHARED}
   LDFLAGS=-L${CMAKE_LIBRARY_OUTPUT_DIRECTORY}
   CYTHON_BUILD_DIR=${CMAKE_BINARY_DIR}/src/pybind/cephfs
   CFLAGS=\"-I${CMAKE_SOURCE_DIR}/src -I${CMAKE_BINARY_DIR}/include -I${CMAKE_SOURCE_DIR}/src/include -std=c++11\"
diff --git a/src/pybind/rados/CMakeLists.txt b/src/pybind/rados/CMakeLists.txt
index 3b2cd38ff38..007ff709555 100644
--- a/src/pybind/rados/CMakeLists.txt
+++ b/src/pybind/rados/CMakeLists.txt
@@ -1,5 +1,9 @@
 add_custom_target(cython_rados
   COMMAND
+  env
+  CC=${PY_CC}
+  CXX=${PY_CXX}
+  LDSHARED=${PY_LDSHARED}
   LDFLAGS=-L${CMAKE_LIBRARY_OUTPUT_DIRECTORY}
   CYTHON_BUILD_DIR=${CMAKE_BINARY_DIR}/src/pybind/rados
   CFLAGS=\"-I${CMAKE_SOURCE_DIR}/src/include -std=c++11\"
diff --git a/src/pybind/rbd/CMakeLists.txt b/src/pybind/rbd/CMakeLists.txt
index b5881530e04..6afc639333d 100644
--- a/src/pybind/rbd/CMakeLists.txt
+++ b/src/pybind/rbd/CMakeLists.txt
@@ -1,5 +1,9 @@
 add_custom_target(cython_rbd
   COMMAND
+  env
+  CC=${PY_CC}
+  CXX=${PY_CXX}
+  LDSHARED=${PY_LDSHARED}
   LDFLAGS=-L${CMAKE_LIBRARY_OUTPUT_DIRECTORY}
   CYTHON_BUILD_DIR=${CMAKE_BINARY_DIR}/src/pybind/rbd
   CFLAGS=\"-I${CMAKE_SOURCE_DIR}/src/include -std=c++11\"