Re: bin/22500: lint breakage for named initializers

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR toolchain/22500; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: bin/22500: lint breakage for named initializers
Date: Sun, 31 Jul 2016 22:35:23 +0000

 On Sun, Mar 30, 2008 at 06:45:02PM +0000, David Holland wrote:
  >     --- 3.c ---
  >  struct {
  >  	struct {
  >  		int b;
  >  	} b;
  >  	struct {
  >  		int d;
  >  	} d;
  >  } bar = {{.b = .d = {0}}};
  >     --- end ---
  >  
  >  % lint -S 3.c
  >  3.c:
  >  lint: /usr/libexec/lint1 got SIGSEGV
 
 This is actually two problems, of which the first no longer crashes
 but instead gives an internal error:
 
    --- 4.c ---
 struct {
    int a;
 } b = {.a = {1}};
    --- end ---
 % lint -S 4.c
 (6): lint error:
 /usr/src/usr.bin/xlint/lint1/init.c, 170: popi2()
 
 and
 
    --- 5.c ---
 struct {
    int a;
 } b = {.c = 3};
    --- end ---
 % lint -S 5.c
 5.c:
 lint: /usr/libexec/lint1 got SIGSEGV
 
 The problem in case 4 is too many braces; it should not accept the
 {1}, or having done so it should fail to match the .a, or something;
 anyway the problem seems to be that closing off the second set of
 braces causes it to want to pop something off that isn't there.
 
 The problem in case 5 is that .c doesn't exist and nothing checks that
 it failed to look up (I guess), so the object has no type and then it
 crashes. The crash happens at line 297 of init.c:
    switch (istk->i_type->t_tspec)
 
 A third problem is that the grammar in cgram.y permits {.a = .b = 3}
 which it shouldn't. This I can fix.
 
 -- 
 David A. Holland
 dholland%netbsd.org@localhost