(funcall (intern "C-CONSTANTS-EXTRACT" (find-package "SB-GROVEL"))
filename tmp-c-source (constants-package component))
(unless (do-not-grovel component)
- (let* ((cc (or (sb-ext:posix-getenv "CC")
+ (let* ((cc (or (and (string/= (sb-ext:posix-getenv "CC") "")
+ (sb-ext:posix-getenv "CC"))
;; It might be nice to include a CONTINUE or
;; USE-VALUE restart here, but ASDF seems to insist
;; on handling the errors itself.