Example with sprintf & %f from cffi manual crashes clisp on cygwin

[Mirko Vukovic]

Hello,

The following example from section 10 of the cffi documentation is causing
a segmentation fault on clisp on cygwin:

(defcfun "sprintf" :int
    (str :pointer)
    (control :string)
    &rest)

  CFFI> (with-foreign-pointer-as-string (s 100)
          (sprintf s "%c %d %.2f %s" :char 90 :short 42 :float 3.1415
                   :string "super-locrian"))
  => "A 42 3.14 super-locrian"


I replaced :float pi with :float 3.1415, as ``pi'' is long-float - I wanted
to remove this as a possible cause.

At first I thought it was the %s for the string, but it may actually be the
%.2f.
- By itself %f, it does not correctly process floats, emitting ``f''.
- If followed by other codes, it swallows them
- If followed by a string, causes a segmentation fault

CL-USER> (cffi:with-foreign-pointer-as-string (s 100)
          (sprintf s "%s"
           :string "super-locrian"))
"super-locrian"

CL-USER> (cffi:with-foreign-pointer-as-string (s 200)
          (sprintf s "%.2f" :float 3.1415))
"f"

CL-USER> (cffi:with-foreign-pointer-as-string (s 200)
          (sprintf s "%.2f %c" :float 3.1415 :char 65))
"f "

CL-USER> (cffi:with-foreign-pointer-as-string (s 200)
          (sprintf s "%.2f %s %c" :float 3.1415 :string "five" :char 65))
Segmentation fault

I'll try this on Linux/SBCL when I get back to work on Monday.

Mirko
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