OSL reference generation test fails

[msuzuki-nvidia]

OSL reference generation test fails for extract node.

Error compiling OSL reference for 'extract' : 
OSL compilation error
Command string: /usr/local/bin/oslc -q  -I"/usr/local/bin/../include"  -I"/home/masuo/Dev/github/msuzuki-nvidia/MaterialX/_build/bin/libraries/stdlib/genosl/include" reference/osl/extract.osl -o reference/osl/extract.oso > reference/osl/extract.oso_compile_errors.txt 2>&1
Command return code: 256
Shader failed to compile:
reference/osl/extract.osl:32: error: Cannot assign vector extract_vector3_matrix33_out = struct vector4
FAILED reference/osl/extract.osl

Error compiling OSL reference for 'extract' : 
OSL compilation error
Command string: /usr/local/bin/oslc -q  -I"/usr/local/bin/../include"  -I"/home/masuo/Dev/github/msuzuki-nvidia/MaterialX/_build/bin/libraries/stdlib/genosl/include" reference/osl/extract.osl -o reference/osl/extract.oso > reference/osl/extract.oso_compile_errors.txt 2>&1
Command return code: 256
Shader failed to compile:
reference/osl/extract.osl:32: error: Cannot assign vector extract_vector3_integer_out = struct vector4
FAILED reference/osl/extract.osl