added new flag: cmodule.compilation_warning

doc/library/config.txt

@@ -621,3 +621,9 @@ import theano and print the config variable, as in:
     If True, will remove -O* parameter passed to g++.
     This is useful to debug in gdb module compiled by Theano.
     The parameter -g is passed by default to g++.
+
+.. attribute:: cmodule.compilation_warning
+
+    Bool value, default: False
+
+    If True, will print compilation warning.

theano/gof/cmodule.py

@@ -48,6 +48,10 @@ AddConfigVar('cmodule.remove_gxx_opt',
              "The parameter -g is passed by default to g++",
              BoolParam(False))
 
+AddConfigVar('cmodule.compilation_warning',
+             "If True, will print compilation warning.",
+             BoolParam(False))
+
 
 def local_bitwidth():
     """
@@ -1578,6 +1582,9 @@ class GCC_compiler(object):
             # difficult to read.
             raise Exception('Compilation failed (return status=%s): %s' %
                             (status, compile_stderr.replace('\n', '. ')))
+        elif config.cmodule.compilation_warning and compile_stderr:
+            # Print errors just below the command line.
+            print compile_stderr
 
         #touch the __init__ file
         file(os.path.join(location, "__init__.py"), 'w').close()

theano/sandbox/cuda/nvcc_compiler.py

@@ -325,6 +325,8 @@ class NVCC_compiler(object):
                 print >> sys.stderr,  i + 1, l
             raise Exception('nvcc return status', p.returncode,
                             'for cmd', ' '.join(cmd))
+        elif config.cmodule.compilation_warning and nvcc_stdout:
+            print nvcc_stdout
 
         #touch the __init__ file
         file(os.path.join(location, "__init__.py"), 'w').close()