fix a bug when gcc segfault when compile the convop with -O3 when the kernel shape is 1,1.

theano/gof/cmodule.py

@@ -579,6 +579,14 @@ def std_libs():
 def std_lib_dirs():
     return std_lib_dirs_and_libs()[1]
 
+p=subprocess.Popen(['gcc','-dumpversion'],stdout=subprocess.PIPE)
+p.wait()
+gcc_version_str = p.stdout.readline().strip()
+del p
+
+def gcc_version():
+    return gcc_version_str
+
 def gcc_module_compile_str(module_name, src_code, location=None, include_dirs=[], lib_dirs=[], libs=[],
         preargs=[]):
     """

theano/tensor/nnet/conv.py

@@ -100,6 +100,21 @@ class ConvOp(Op):
             'imshp_logical', 'kshp_logical', 'kshp_logical_top_aligned']
     """These attributes uniquely identify the behaviour of this op for given inputs"""
 
+    
+    def c_compile_args(self):
+        #when the ksph==(1,1) gcc 4.3.0 segfault during the compilation with -O3.
+        #This don't happen at -O2
+        if theano.gof.cmodule.gcc_version() in ['4.3.0'] and self.kshp==(1,1):
+            return ['-O2']
+        else: return []
+
+    def c_no_compile_args(self):
+        #when the ksph==(1,1) gcc 4.3.0 segfault during the compilation with -O3.
+        #This don't happen at -O2
+        if theano.gof.cmodule.gcc_version() in ['4.3.0'] and self.kshp==(1,1):
+            return ['-O3']
+        else: return []
+
     @staticmethod
     def getOutputShape(inshp, kshp, (dx,dy)=(1,1), mode='valid'):
         """