Re: An g++ exception bug in egcs 970924

Re: An g++ exception bug in egcs 970924

[Jason Merrill]

Nested exceptions are not supported.

Jason

Re: An g++ exception bug in egcs 970924

[H.J. Lu]

> 
> Nested exceptions are not supported.
> 
> Jason
> 

Here is a real exception bug on x86.

# gcc -O des.cc -fno-exceptions
# a.out
# gcc -O des.cc
# a.out
zsh: 9138 segmentation fault  ./a.out

There may be more bugs like that.

-- 
H.J. Lu (hjl@gnu.ai.mit.edu)
---
class Int 
{
protected:
  int          rep;
public: 
  Int () :rep(0) {}
  Int (const Int& b) :rep(b.Int::val()) {}
  ~Int();
  operator int() const { return val(); }
  int   val() const { return rep; }
  void  operator  = (const int b)
  { rep = b; }
  void  operator ++ ()
  { ++rep; }
};
Int::~Int() {}
void Proc0();
void Proc7(Int IntParI1, Int IntParI2, Int *IntParOut);
main()
{
	Proc0();
	exit(0);
}
void Proc0()
{
	Int		IntLoc1;
	Int		IntLoc2;
	Int		IntLoc3;
	IntLoc1 = 2;
	IntLoc2 = 3;
	while (IntLoc1 < IntLoc2)
	{
		IntLoc3 = 5 * IntLoc1 - IntLoc2;
		Proc7(IntLoc1, IntLoc2, &IntLoc3);
		++IntLoc1;
	}
}
void Proc7(Int IntParI1, Int IntParI2, Int *IntParOut)
{
	Int	IntLoc;
	IntLoc = IntParI1 + 2;
	*IntParOut = IntParI2 + IntLoc;
}

An g++ exception bug in egcs 970924

[H.J. Lu]

egcs 970924 configured for linux/x86/libc 5.

# gcc g++.mike/eh35.C
# a.out
zsh: 6096 segmentation fault  ./a.out


-- 
H.J. Lu (hjl@gnu.ai.mit.edu)
---g++.mike/eh35.C---
// Special g++ Options: -fexceptions
// excess errors test - XFAIL a29k-*-* sparc64-*-elf sh-*-* arm-*-pe**-*

main() {
  try {  
    throw 'a';
  } catch (char a) {
    try {
      throw 'a';
    } catch (int i) {
      return 1;
    } catch (char c) {
      return 0;
    }
  }
  return 1;
}