Index: numcodecs-0.11.0/setup.py
===================================================================
--- numcodecs-0.11.0.orig/setup.py
+++ numcodecs-0.11.0/setup.py
@@ -104,6 +104,7 @@ def blosc_extension():
         Extension('numcodecs.blosc',
                   sources=sources + blosc_sources,
                   include_dirs=include_dirs,
+                  libraries=[] if blosc_sources else ['blosc'],
                   define_macros=define_macros,
                   extra_compile_args=extra_compile_args,
                   ),
@@ -138,6 +139,7 @@ def zstd_extension():
         Extension('numcodecs.zstd',
                   sources=sources + zstd_sources,
                   include_dirs=include_dirs,
+                  libraries=[] if zstd_sources else ['zstd'],
                   define_macros=define_macros,
                   extra_compile_args=extra_compile_args,
                   ),
@@ -165,6 +167,7 @@ def lz4_extension():
         Extension('numcodecs.lz4',
                   sources=sources + lz4_sources,
                   include_dirs=include_dirs,
+                  libraries=[] if lz4_sources else ['lz4'],
                   define_macros=define_macros,
                   extra_compile_args=extra_compile_args,
                   ),
Index: numcodecs-0.11.0/numcodecs/tests/test_blosc.py
===================================================================
--- numcodecs-0.11.0.orig/numcodecs/tests/test_blosc.py
+++ numcodecs-0.11.0/numcodecs/tests/test_blosc.py
@@ -155,10 +155,11 @@ def test_compress_complib(use_threads):
     }
     blosc.use_threads = use_threads
     for cname in blosc.list_compressors():
-        enc = blosc.compress(arr, cname.encode(), 1, Blosc.NOSHUFFLE)
-        complib = blosc.cbuffer_complib(enc)
-        expected_complib = expected_complibs[cname]
-        assert complib == expected_complib
+        if cname in expected_complibs:
+            enc = blosc.compress(arr, cname.encode(), 1, Blosc.NOSHUFFLE)
+            complib = blosc.cbuffer_complib(enc)
+            expected_complib = expected_complibs[cname]
+            assert complib == expected_complib
     with pytest.raises(ValueError):
         # capitalized cname
         blosc.compress(arr, b'LZ4', 1)