[ruby-core:58667] [ruby-trunk - Bug #9173] rb_sprintf %li format specifier does not work correctly with long values and can cause Ruby to crash

Issue #9173 has been updated by jeremyevans0 (Jeremy Evans).


This is now expected behavior.  %i starting in 2.0 means you need to provide a ruby object (VALUE) argument, not an integer.  You need to switch from %li to %ld.
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Bug #9173: rb_sprintf %li format specifier does not work correctly with long values and can cause Ruby to crash
https://bugs.ruby-lang.org/issues/9173#change-43235

Author: bladenkerst (Brad Sumersford)
Status: Open
Priority: Low
Assignee: 
Category: 
Target version: 
ruby -v: ruby 2.0.0p195
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN


There is additional handling of %i versus %d in BSD_vfprintf (>= 2.0).  When l (long) is specified as the length, %li, the additional handling is triggered.
Note: %ld works fine, %li and %ld work in Ruby 1.9.3

Sample Code:

## sprintf_test.c

#include "ruby.h"

static VALUE 
sprintfTest(VALUE module, VALUE fix) {
  Check_Type(fix, T_FIXNUM);

  long long_value = FIX2LONG(fix);
  VALUE back_to_ruby = LONG2FIX(long_value);

  printf("This should show the correct value: %li\n", long_value);
  rb_funcall(rb_mKernel, rb_intern("puts"), 2, rb_str_new2("This should also show the correct value: "), back_to_ruby);

  return rb_sprintf("This will return the wrong value, or crash: %li", long_value);
}

void Init_sprintf() {
  rb_define_method(rb_mKernel, "sprintf_test", sprintfTest, 1);  
}

## irb

require './sprintf'

irb(main):004:0> sprintf_test 3
This should show the correct value: 3
This should also show the correct value: 
3
=> "This will return the wrong value, or crash: 1"

irb(main):004:0> sprintf_test 3
This should show the correct value: 3
This should also show the correct value: 
3

irb(main):004:0> sprintf_test 4
This should show the correct value: 4
This should also show the correct value: 
4
(irb):4: [BUG] Segmentation fault
ruby 2.0.0p195 (2013-05-14) [x86_64-darwin10.8.0]




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