Bug#470557: smaller testcase for gcc misoptimization bug

[Török Edwin <edwin@clamav.net>]

Package: gcc-4.2
Version: 4.2.3-2

--- Please enter the report below this line. ---

I have manually reduced the previous testcase (it is 4K now, vs 32K).

The same testcase can be used for both x86_64 and x86(-32).

When I compile with -O3, or -O2 -finline-functions incorrect code is
generated.

$ gcc-4.2 -O2 -finline-functions gcc42_O3_bug.i
$ ./a.out
Aborted
$ gcc-4.2 -O2 gcc42_O3_bug.i
$ ./a.out
$ valgrind ./a.out
....
==11486== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 8 from 1)
.....

$ sh -x ./test.sh gcc42_O3_bug.i
+ gcc-4.3 -fstack-protector-all -O1 -Wfatal-errors -Werror
-Wno-unused gcc42_O3_bug.i -o works3
+ test 0 == 0
+ ulimit -t 1
+ ./works3
+ test 0 == 0
+ gcc-4.2 -Wall -Wfatal-errors -Werror -Wno-unused -O3
gcc42_O3_bug.i -o fails
+ test 0 == 0
+ ulimit -t 1
+ ./fails
./test.sh: line 24: 11426 Aborted                 ./fails 2>/dev/null
+ test 134 == 134
+ exit 0

If you need more info, please ask.

--- System information. ---
Architecture: amd64
Kernel:       Linux 2.6.25-rc4-00134-g84c6f60

Debian Release: lenny/sid
  500 unstable        www.debian-multimedia.org
  500 unstable        ftp.iasi.roedu.net
  500 testing         ftp.iasi.roedu.net
  500 gutsy           wine.budgetdedicated.com
    1 experimental    ftp.iasi.roedu.net

--- Package information. ---
Depends                     (Version) | Installed
=====================================-+-=====================
binutils         (>= 2.17cvs20070426) | 2.18.1~cvs20080103-1
cpp-4.2                   (= 4.2.3-2) | 4.2.3-2
gcc-4.2-base              (= 4.2.3-2) | 4.2.3-2
libc6                      (>= 2.7-1) | 2.7-9
libgcc1                (>= 1:4.2.3-2) | 1:4.3.0-1

typedef unsigned long int uint64_t;
       void cli_dbgmsg_internal(const char *str,...) {
      }
       typedef long unsigned int size_t;
       extern int memcmp (__const void *__s1, __const void *__s2, size_t __n)   __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__ ((__nonnull__ (1, 2)));
       extern void abort (void) __attribute__ ((__nothrow__)) __attribute__ ((__noreturn__));
       unsigned char data[] = {
            0x50, 0x4d, 0x47, 0x4c, 0x38, 0x01, 0x00, 0x00, 0x63, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x01, 0x2f, 0x00, 0x00, 0x00, 0x06, 0x2f, 0x23, 0x42, 0x53, 0x53, 0x43, 0x01, 0x88, 0x90, 0x79, 0x09, 0x08, 0x2f, 0x23, 0x49, 0x44, 0x58, 0x48, 0x44, 0x52, 0x01, 0xc0, };
                 typedef long int __off_t;
                 typedef __off_t off_t;
                 typedef unsigned char uint8_t;
                 typedef unsigned short int uint16_t;
                 typedef unsigned int uint32_t;
                 uint8_t cli_debug_flag=0, cli_leavetemps_flag;
                 typedef struct chm_itsf_header_tag {
             uint32_t block_len __attribute__ ((packed));
            }
                 chm_itsp_header_t;
                 typedef struct chm_metadata_tag {
             char *m_area;
             chm_itsp_header_t itsp_hdr;
             off_t chunk_offset;
             char *chunk_data;
             char *chunk_current;
             char *chunk_end;
             uint16_t chunk_entries;
            }
                 chm_metadata_t;
               int cli_chm_open( chm_metadata_t *metadata);
                 int cli_chm_prepare_file(int fd, chm_metadata_t *metadata);
                 static uint64_t read_enc_int(char **start, char *end) {
             uint64_t retval=0;
             char *current;
             current = *start;
             do {
         retval = (retval << 7) | (*current & 0x7f);
        }
            while (*current++ & 0x80);
             *start = current;
             return retval;
            }
       static int prepare_file(int fd, chm_metadata_t *metadata) {
     	uint64_t name_len, section;
     	while (metadata->chunk_entries != 0) {
   		if (metadata->chunk_current >= metadata->chunk_end) {
 		}
   		name_len = read_enc_int(&metadata->chunk_current, 				metadata->chunk_end);
   	  	if (((metadata->chunk_current + name_len) >= metadata->chunk_end) ||     ((metadata->chunk_current + name_len) < metadata->chunk_data)) {
 		    	(!__builtin_expect(!!(cli_debug_flag), 					   0)) ? (void)0 : cli_dbgmsg_internal("Bad CHM name_len detected\n");
 		}
   		metadata->chunk_current += name_len;
   		section = read_enc_int(&metadata->chunk_current, 				metadata->chunk_end);
   		if(section == 47) {
 			abort();
 		}
   		if (section == 1) {
 			return 0;
 		}
   	}
     	return 0;
     }
       static int read_chunk(chm_metadata_t *metadata, int fd) {
     	if (metadata->m_area != ((void *)0)) {
   		metadata->chunk_data = metadata->m_area + metadata->chunk_offset;
   	}
     	metadata->chunk_current = metadata->chunk_data + (0x14);
     	if (memcmp(metadata->chunk_data, "PMGL", 4) == 0) {
   		metadata->chunk_entries = (uint16_t)((((uint8_t const *)(metadata->chunk_data))[metadata->itsp_hdr.block_len-2] << 0)      | (((uint8_t const *)(metadata->chunk_data))[metadata->itsp_hdr.block_len-1] << 8));
   	}
     	return 0;
     }
       int main() {
     	int ret;
     	chm_metadata_t metadata;
     	ret = cli_chm_open(&metadata);
     	ret = cli_chm_prepare_file(-1, 			&metadata);
     	return 0;
     }
       int cli_chm_prepare_file(int fd,  chm_metadata_t *metadata) {
     	int retval;
     	metadata->chunk_entries=0;
     	do {
   		if (metadata->chunk_entries == 0) {
 			if ((retval = read_chunk(metadata, fd)) != 0) {
 			}
 		}
   		retval = prepare_file(fd, metadata);
   	}
     	while (retval == 2);
     	return 0;
     }
       int cli_chm_open(chm_metadata_t *metadata) {
     	metadata->m_area = (char*)data;
     	metadata->itsp_hdr.block_len = 0x0a;
     	metadata->chunk_offset = 0;
   	return 0;
     }