Add a check to a list of subdirectories to include libwarpctc in c_lib_dirs

theano/configdefaults.py

@@ -1773,8 +1773,8 @@ AddConfigVar(
 AddConfigVar(
     'ctc.root',
     'Directory which contains the root of Baidu CTC library. It is assumed \
-    that the compiled library is inside the build directory, and the header \
-    inside the include directory.',
+    that the compiled library is either inside the build, lib or lib64 \
+    subdirectory, and the header inside the include directory.',
     StrParam('', allow_override=False))
 
 # Check if there are remaining flags provided by the user through THEANO_FLAGS.

theano/gpuarray/ctc.py

@@ -13,6 +13,7 @@ from theano.tensor.opt import register_canonicalize
 from theano.tensor.opt import register_stabilize
 
 import os
+import os.path
 from . import pygpu
 
 ctc_enabled = config.ctc.enabled
@@ -53,9 +54,19 @@ class GpuConnectionistTemporalClassification(gof.COp):
     def c_lib_dirs(self):
         dirs = []
         if ctc_enabled:
-            # We assume here that the compiled library (libwarpctc.so) is available
-            # at the build directory of the CTC root directory.
-            dirs.append(os.path.join(config.ctc.root, "build"))
+            # Find the directory that contains libwarpctc.so
+            lib_found = False
+            for lib_dir in ["build", "lib", "lib64"]:
+                lib_path = os.path.join(config.ctc.root, lib_dir)
+                if os.path.isdir(lib_path) and os.path.exists(lib_path):
+                    lib_found = os.path.exists(os.path.join(lib_path, "libwarpctc.so"))
+                    if lib_found:
+                        dirs.append(lib_path)
+                        break
+
+            if not lib_found:
+                raise RuntimeError('libwarpctc.so could not be found. ',
+                                   'Please check the config.ctc.root variable.')
         return dirs
 
     def c_libraries(self):

theano/tensor/nnet/ctc.py

 from __future__ import (division, absolute_import, print_function)
 import os
+import os.path
 import theano.tensor as T
 from theano import config
 from theano import gof
@@ -53,9 +54,19 @@ class ConnectionistTemporalClassification(gof.COp, gof.OpenMPOp):
     def c_lib_dirs(self):
         dirs = []
         if ctc_enabled:
-            # We assume here that the compiled library (libwarpctc.so) is available
-            # at the build directory of the CTC root directory.
-            dirs.append(os.path.join(config.ctc.root, "build"))
+            # Find the directory that contains libwarpctc.so
+            lib_found = False
+            for lib_dir in ["build", "lib", "lib64"]:
+                lib_path = os.path.join(config.ctc.root, lib_dir)
+                if os.path.isdir(lib_path) and os.path.exists(lib_path):
+                    lib_found = os.path.exists(os.path.join(lib_path, "libwarpctc.so"))
+                    if lib_found:
+                        dirs.append(lib_path)
+                        break
+
+            if not lib_found:
+                raise RuntimeError('libwarpctc.so could not be found. ',
+                                   'Please check the config.ctc.root variable.')
         return dirs
 
     def c_libraries(self):