Allow the Thrift compiler to be built without the C++ generator.

- Use AX_THRIFT_GEN to make configure support --disable-gen-cpp
- Update the compiler Makefile.am to exclude the generator.


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665516 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/compiler/cpp/Makefile.am b/compiler/cpp/Makefile.am
index b23a22a..1c47657 100644
--- a/compiler/cpp/Makefile.am
+++ b/compiler/cpp/Makefile.am
@@ -9,7 +9,6 @@
                  src/main.cc \
                  src/md5c.c \
                  src/generate/t_generator.cc \
-                 src/generate/t_cpp_generator.cc \
                  src/generate/t_java_generator.cc \
                  src/generate/t_php_generator.cc \
                  src/generate/t_py_generator.cc \
@@ -58,6 +57,10 @@
                  src/generate/t_st_generator.h \
                  src/generate/t_csharp_generator.h
 
+if THRIFT_GEN_cpp
+thrift_SOURCES += src/generate/t_cpp_generator.cc
+endif
+
 thrift_CXXFLAGS = -Wall -I$(srcdir)/src $(BOOST_CPPFLAGS)
 thrift_LDFLAGS = -Wall $(BOOST_LDFLAGS)
 
diff --git a/configure.ac b/configure.ac
index 96329ce..13f0d8e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -113,6 +113,9 @@
 AC_CHECK_FUNCS([strtol])
 AC_CHECK_FUNCS([sqrt])
 
+AX_THRIFT_GEN(cpp, [C++], yes)
+AM_CONDITIONAL([THRIFT_GEN_cpp], [test "$ax_thrift_gen_cpp" = "yes"])
+
 AC_CONFIG_HEADERS(config.h:config.hin)
 
 AC_CONFIG_FILES([