The default target is SPIR-V 1.3.
For example, spirv-as will generate a SPIR-V 1.3 binary by default.
Use command line option "--target-env spv1.0" if you want to make a SPIR-V
1.0 binary or validate against SPIR-V 1.0 rules.
Example:
# Generate a SPIR-V 1.0 binary instead of SPIR-V 1.3
spirv-as --target-env spv1.0 a.spvasm -o a.spv
spirv-as --target-env vulkan1.0 a.spvasm -o a.spv
# Validate as SPIR-V 1.0.
spirv-val --target-env spv1.0 a.spv
# Validate as Vulkan 1.0
spirv-val --target-env vulkan1.0 a.spv