CMakeLists.txt - turn-on C++ bindings only if a C++ compiler is found

part of issue#352

2 files changed, 15 insertions, 6 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1cc7180e..5bcda64a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -71,7 +71,7 @@
 #
 
 cmake_minimum_required(VERSION 3.1.0) #first line, to shutup a cygwin warning
-project(libical C CXX)
+project(libical C) #CXX is optional for the bindings
 
 cmake_policy(SET CMP0003 NEW)
 if(POLICY CMP0042)
@@ -538,14 +538,22 @@ endif()
 ########################################################
 
 option(WITH_CXX_BINDINGS "Build the C++ bindings." True)
+if(WITH_CXX_BINDINGS)
+  if(CMAKE_CXX_COMPILER)
+    add_definitions(-DWITH_CXX_BINDINGS)
+  else()
+    message(STATUS
+      "Warning: Building the C++ bindings is not possible since a C++ compiler could not be found. "
+      "Turning-off C++ bindings"
+    )
+    set(WITH_CXX_BINDINGS False)
+  endif()
+endif()
 add_feature_info(
   "Option WITH_CXX_BINDINGS"
   WITH_CXX_BINDINGS
-  "build the C++ bindings"
+  "build the C++ bindings. Requires a C++ compiler"
 )
-if(WITH_CXX_BINDINGS)
-  add_definitions(-DWITH_CXX_BINDINGS)
-endif()
 
 #some test programs need to know if we are using 32-bit time
 if(SIZEOF_TIME_T EQUAL 4)
diff --git a/Install.txt b/Install.txt
index 1ba87063..71fedff1 100644
--- a/Install.txt
+++ b/Install.txt
@@ -103,8 +103,9 @@ For instance:
 
 == Language Bindings ==
 This C library can be built with bindings for these other languages:
-* C++. By default the buildsystem will create and install the C++ bindings API.
+* C++. If a C++ compiler is found the buildsystem will create and install the C++ bindings API.
   Turn this off by passing -DWITH_CXX_BINDINGS=False option to CMake.
+  Don't mix ABI from C and C++ compilers.
 
 * There are Java, Perl, PHP and Python bindings but they are old and haven't
   been tested in a very long time.  Volunteers wanted.