[ N.B. This bug strikes on a Sun 3 running SunOS 4 with the cc -O4 option as well as on the sparc. -Mike ] Date: Fri, 24 Feb 89 15:36:40 -0600 To: mike@wheaties.ai.mit.edu From: Dave Cohrs Subject: bug + fix in gnu grep 1.2 (from prep.ai.mit.edu) I tried installing the GNU grep 1.2 on a Sun4 running 4.0.1 and "Spencer test #36" failed. After some experimenting, I found and fixed the bug. Well, actually, the bug in the the C compiler, but I managed a workaround. Description: The Sun4 4.0.1 C compiler with -O doesn't generate the correct for statements of the form if("string") x; else y; To be exact, "y;" gets executed, while "x;" should. This causes the #define FETCH() to fail for test #36. Fix: In an #ifdef sparc in dfa.c, I made two versions of FETCH, FETCH0() and the regular FETCH(). The former takes only one argument, the latter expects its 2nd argument to contain a non-nil string. This removes the need to test the constant strings, and the compiler bug isn't exercised. I then changed the one instance of FETCH() with a nil second argument to be FETCH0() instead. dave cohrs =================================================================== RCS file: RCS/dfa.c,v retrieving revision 1.1 diff -c -r1.1 dfa.c *** /tmp/,RCSt1a05930 Fri Feb 24 15:32:33 1989 --- dfa.c Fri Feb 24 15:23:34 1989 *************** *** 285,293 **** --- 285,315 ---- is turned off). */ /* Note that characters become unsigned here. */ + #ifdef sparc + /* + * Sun4 4.0.1 C compiler can't compare constant strings correctly. + * e.g. if("test") { x; } else { y; } + * the compiler will not generate code to execute { x; }, but + * executes { y; } instead. + */ + #define FETCH0(c) \ + { \ + if (! lexleft) \ + return _END; \ + (c) = (unsigned char) *lexptr++; \ + --lexleft; \ + } #define FETCH(c, eoferr) \ { \ if (! lexleft) \ + regerror(eoferr); \ + (c) = (unsigned char) *lexptr++; \ + --lexleft; \ + } + #else + #define FETCH(c, eoferr) \ + { \ + if (! lexleft) \ if (eoferr) \ regerror(eoferr); \ else \ *************** *** 295,300 **** --- 317,323 ---- (c) = (unsigned char) *lexptr++; \ --lexleft; \ } + #endif sparc static _token lex() *************** *** 303,309 **** --- 326,336 ---- int invert; _charset cset; + #ifdef sparc + FETCH0(c); + #else FETCH(c, (char *) 0); + #endif sparc switch (c) { case '^':