* gnu/packages/rust.scm (rust-1.26)[arguments]<#:phases>[check]: Enable
parallel tests.
`(modify-phases ,phases
;; binaryen was replaced with LLD project from LLVM
(delete 'dont-build-native)
+ (replace 'check
+ (lambda* _
+ ;; Enable parallel execution.
+ (let ((parallel-job-spec
+ (string-append "-j" (number->string
+ (min 4
+ (parallel-job-count))))))
+ (invoke "./x.py" parallel-job-spec "test" "-vv")
+ (invoke "./x.py" parallel-job-spec "test"
+ "src/tools/cargo"))))
(replace 'remove-unsupported-tests
(lambda* _
;; Our ld-wrapper cannot process non-UTF8 bytes in LIBRARY_PATH.