projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 83803754 WJ |
1 | [ N.B. This bug strikes on a Sun 3 running SunOS 4 with the cc -O4 option |
| 2 | as well as on the sparc. -Mike ] | |
| 3 | ||
| 4 | Date: Fri, 24 Feb 89 15:36:40 -0600 | |
| 5 | To: mike@wheaties.ai.mit.edu | |
| 6 | From: Dave Cohrs <dave@cs.wisc.edu> | |
| 7 | Subject: bug + fix in gnu grep 1.2 (from prep.ai.mit.edu) | |
| 8 | ||
| 9 | I tried installing the GNU grep 1.2 on a Sun4 running 4.0.1 and | |
| 10 | "Spencer test #36" failed. After some experimenting, I found and | |
| 11 | fixed the bug. Well, actually, the bug in the the C compiler, but | |
| 12 | I managed a workaround. | |
| 13 | ||
| 14 | Description: | |
| 15 | ||
| 16 | The Sun4 4.0.1 C compiler with -O doesn't generate the correct for | |
| 17 | statements of the form | |
| 18 | if("string") | |
| 19 | x; | |
| 20 | else | |
| 21 | y; | |
| 22 | To be exact, "y;" gets executed, while "x;" should. This causes the | |
| 23 | #define FETCH() to fail for test #36. | |
| 24 | ||
| 25 | Fix: | |
| 26 | ||
| 27 | In an #ifdef sparc in dfa.c, I made two versions of FETCH, FETCH0() and | |
| 28 | the regular FETCH(). The former takes only one argument, the latter | |
| 29 | expects its 2nd argument to contain a non-nil string. This removes | |
| 30 | the need to test the constant strings, and the compiler bug isn't | |
| 31 | exercised. I then changed the one instance of FETCH() with a nil | |
| 32 | second argument to be FETCH0() instead. | |
| 33 | ||
| 34 | dave cohrs | |
| 35 | ||
| 36 | =================================================================== | |
| 37 | RCS file: RCS/dfa.c,v | |
| 38 | retrieving revision 1.1 | |
| 39 | diff -c -r1.1 dfa.c | |
| 40 | *** /tmp/,RCSt1a05930 Fri Feb 24 15:32:33 1989 | |
| 41 | --- dfa.c Fri Feb 24 15:23:34 1989 | |
| 42 | *************** | |
| 43 | *** 285,293 **** | |
| 44 | --- 285,315 ---- | |
| 45 | is turned off). */ | |
| 46 | ||
| 47 | /* Note that characters become unsigned here. */ | |
| 48 | + #ifdef sparc | |
| 49 | + /* | |
| 50 | + * Sun4 4.0.1 C compiler can't compare constant strings correctly. | |
| 51 | + * e.g. if("test") { x; } else { y; } | |
| 52 | + * the compiler will not generate code to execute { x; }, but | |
| 53 | + * executes { y; } instead. | |
| 54 | + */ | |
| 55 | + #define FETCH0(c) \ | |
| 56 | + { \ | |
| 57 | + if (! lexleft) \ | |
| 58 | + return _END; \ | |
| 59 | + (c) = (unsigned char) *lexptr++; \ | |
| 60 | + --lexleft; \ | |
| 61 | + } | |
| 62 | #define FETCH(c, eoferr) \ | |
| 63 | { \ | |
| 64 | if (! lexleft) \ | |
| 65 | + regerror(eoferr); \ | |
| 66 | + (c) = (unsigned char) *lexptr++; \ | |
| 67 | + --lexleft; \ | |
| 68 | + } | |
| 69 | + #else | |
| 70 | + #define FETCH(c, eoferr) \ | |
| 71 | + { \ | |
| 72 | + if (! lexleft) \ | |
| 73 | if (eoferr) \ | |
| 74 | regerror(eoferr); \ | |
| 75 | else \ | |
| 76 | *************** | |
| 77 | *** 295,300 **** | |
| 78 | --- 317,323 ---- | |
| 79 | (c) = (unsigned char) *lexptr++; \ | |
| 80 | --lexleft; \ | |
| 81 | } | |
| 82 | + #endif sparc | |
| 83 | ||
| 84 | static _token | |
| 85 | lex() | |
| 86 | *************** | |
| 87 | *** 303,309 **** | |
| 88 | --- 326,336 ---- | |
| 89 | int invert; | |
| 90 | _charset cset; | |
| 91 | ||
| 92 | + #ifdef sparc | |
| 93 | + FETCH0(c); | |
| 94 | + #else | |
| 95 | FETCH(c, (char *) 0); | |
| 96 | + #endif sparc | |
| 97 | switch (c) | |
| 98 | { | |
| 99 | case '^': |