| # Make a local copy of the substitutions. | |
| config.substitutions = list(config.substitutions) | |
| config.substitutions.insert(0, ('%build-irgen-test-overlays', | |
| '%target-swift-frontend -emit-module -o %t -sdk %S/Inputs %S/Inputs/ObjectiveC.swift && ' | |
| '%target-swift-frontend -emit-module -o %t -sdk %S/Inputs %S/Inputs/Foundation.swift -I %t')) |