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
Mirko Vukovic mirko.vukovic@gmail.com writes:
The following example from section 10 of the cffi documentation is causing a segmentation fault on clisp on cygwin:
The varargs support in CFFI makes some assumptions that might not be true on Windows, I suppose. Is this x86 or x86-64?
Cheers, Luís
On Mon, Jul 1, 2013 at 9:04 AM, Luís Oliveira luismbo@gmail.com wrote:
Mirko Vukovic mirko.vukovic@gmail.com writes:
The following example from section 10 of the cffi documentation is causing a segmentation fault on clisp on cygwin:
The varargs support in CFFI makes some assumptions that might not be true on Windows, I suppose. Is this x86 or x86-64?
It's complicated:
- The machine is X86-64 running Windows 7 - I am using clisp 2.48 which is part of the cygwin distribution - cygwin is 32-bit - I assume that clisp is also 32 bit - The version of gcc (for what it's worth) is 4.5.3
Mirko
On Mon, Jul 1, 2013 at 9:24 AM, Mirko Vukovic mirko.vukovic@gmail.comwrote:
On Mon, Jul 1, 2013 at 9:04 AM, Luís Oliveira luismbo@gmail.com wrote:
Mirko Vukovic mirko.vukovic@gmail.com writes:
The following example from section 10 of the cffi documentation is causing a segmentation fault on clisp on cygwin:
The varargs support in CFFI makes some assumptions that might not be true on Windows, I suppose. Is this x86 or x86-64?
It's complicated:
- The machine is X86-64 running Windows 7
- I am using clisp 2.48 which is part of the cygwin distribution
- cygwin is 32-bit
- I assume that clisp is also 32 bit
- The version of gcc (for what it's worth) is 4.5.3
Mirko
Your comment brings to mind another issue I had. I was trying to fetch a signed integer 32 variable that contained error codes. But I was getting large negative numbers. I only got reasonable results when I set the cffi code to look for an unsigned integer 32 variable. Maybe the two issues are related.
Mirko
Mirko Vukovic mirko.vukovic@gmail.com writes:
Your comment brings to mind another issue I had. I was trying to fetch a signed integer 32 variable that contained error codes. But I was getting large negative numbers. I only got reasonable results when I set the cffi code to look for an unsigned integer 32 variable. Maybe the two issues are related.
Running the test suite should be a good way to weed out basic (possibly platform-specific) bugs in CLISP or CFFI. You'll have to manually compile libtest, I think. (Haven't tested with cygwin in several years.)
Cheers, Luís
On Mon, Jul 1, 2013 at 11:27 AM, Luís Oliveira luismbo@gmail.com wrote:
Mirko Vukovic mirko.vukovic@gmail.com writes:
Your comment brings to mind another issue I had. I was trying to fetch a signed integer 32 variable that contained error codes. But I was getting large negative numbers. I only got reasonable results when I set the cffi code to look for an unsigned integer 32 variable. Maybe the two issues are related.
Running the test suite should be a good way to weed out basic (possibly platform-specific) bugs in CLISP or CFFI. You'll have to manually compile libtest, I think. (Haven't tested with cygwin in several years.)
Cheers, Luís
Good idea. I have a long weekend coming. Perfect relaxation :-)
-
Luís Oliveira -
Mirko Vukovic