ref #3215
If a function (such as mrb_read_irep_file()) is declared without MRB_API
in header file (such as include/mruby/dump.h), implementation of the
function in source file (such as src/load.c) should also defined without
MRB_API.
If MRB_API is mismatch, Visual C++ reports link error with C2375 error
code: https://msdn.microsoft.com/en-us/library/5k6kw95a.aspx
mrb_vm_define_class() may realloc() mrb->c->stack because it calls
mrb_funcall() for inherited hook. If mrb->c->stack is realloc()-ed, regs
refers orphan address.
GitHub: fix#3122
It reverts #3126. #3126 fixes the segmentation fault but generates
broken backtrace.
This change fixes the segmentation fault and generates correct
backtrace. The strategy of this change is "generating backtrace while
irep is alive".
/tmp/test.rb:
def gen
e0 = nil
begin
1.times {
raise 'foobar'
}
rescue => e
e0 = e
end
e0
end
e = gen
GC.start
gen
GC.start
puts e.backtrace.join("\n")
Run:
% bin/mruby /tmp/test.rb
/tmp/test.rb:5:in Object.gen
/home/kou/work/ruby/mruby.kou/mrblib/numeric.rb:77:in Integral#times
/tmp/test.rb:4:in Object.gen
/tmp/test.rb:13
FYI:
% ruby -v /tmp/test.rb
ruby 2.3.0p0 (2015-12-25) [x86_64-linux-gnu]
/tmp/test.rb:5:in `block in gen'
/tmp/test.rb:4:in `times'
/tmp/test.rb:4:in `gen'
/tmp/test.rb:13:in `<main>'
It looks like the logic to reallocate the backtrace was flawed,
based on the wrong variable (loc_raw->i, which, as I have verified,
decreases from 16 to 0 instead of increasing)
I am not sure if this is the correct fix
mrb_get_args() keeps pointer of the current stack. But address of the
current stack maybe changed by method call.
'i' format character calls #to_i when the argument isn't integer but
has #to_i.
Here is a code that may call #to_i in mrb_get_args():
case 'i':
// ...
default:
*p = mrb_fixnum(mrb_Integer(mrb, ARGV[arg_i]));
break;
// ...
Here is a code #to_i is called:
class X
def initialize(i)
@i = i
end
def to_i
@i
end
end
[][X.new(0), 0] # X#to_i is called
So, mrb_get_args() shouldn't keep pointer and use it. mrb_get_args()
should always refer mrb->ci->stack to use valid address of the current
stack.
Yukihiro "Matz" Matsumoto