[regehr@bethe tmp604]$ current-gcc -O3 small.c -c -fwhole-program small.c: In function 'main': small.c:42:1: error: invalid operands in binary operation D.2852_11 = (unsigned int) D.2845_7 != 4294967295; small.c:42:1: internal compiler error: verify_stmts failed Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. [regehr@bethe tmp604]$ current-gcc -v Using built-in specs. COLLECT_GCC=current-gcc COLLECT_LTO_WRAPPER=/uusoc/exports/scratch/regehr/z/compiler-install/gcc-r162424-inst all/bin/../libexec/gcc/x86_64-unknown-linux-gnu/4.6.0/lto-wrapper Target: x86_64-unknown-linux-gnu Configured with: ../configure --with-libelf=/usr/local --enable-lto --prefix=/home/re gehr/z/compiler-install/gcc-r162424-install --program-prefix=r162424- --enable-langua ges=c,c++ Thread model: posix gcc version 4.6.0 20100722 (experimental) (GCC) [regehr@bethe tmp604]$ cat small.c typedef signed char int8_t; typedef short int int16_t; typedef int int32_t; typedef unsigned char uint8_t; typedef unsigned int uint32_t; static uint32_t safe_mod_func_uint32_t_u_u (uint32_t ui1, uint8_t ui2) { return ui2 ? ui1 : ui1 + ui2; } int8_t g_2; uint32_t g_36[7][4] = { -1L, -1L, -1L, 0, -1L, -1L, -1L, 0 }; uint8_t g_56; uint8_t g_269; int32_t func_37 (const int16_t p_38, int16_t p_39, int8_t p_40, int32_t p_41, uint8_t p_42); uint8_t func_1 (void) { uint8_t *l_298 = &g_2; func_20 (l_298, &l_298 != &l_298 == ~func_37 (func_37 (g_56, 0, 0, g_269, 0), 1, 0, -1L, 0), 0); return 0; } int32_t func_37 (const int16_t p_38, int16_t p_39, int8_t p_40, int32_t p_41, uint8_t p_42) { uint8_t *l_55 = &g_56; *l_55 |= g_2 < safe_mod_func_uint32_t_u_u (g_36[1][2], 0) | 0, ~p_39; return 0; } int main (int argc, char *argv[]) { func_1 (); }
Caused by tree-ssa-reassoc.c
Simplified testcase: typedef unsigned int T; extern void foo (unsigned char *, int); static signed char a; static T b[1] = { -1 }; static unsigned char c; static inline short int bar (short v) { c |= a < b[0]; return 0; } int main () { unsigned char *e = &a; foo (e, bar (bar (c))); return 0; }
Works if b[] has unsigned int type instead of T. Sounds like a type mismatch. The VAR_DECL b has ARRAY_TYPE with T element type and b's CONSTRUCTOR has the same type, but the values in the constructor doesn't have T type, but unsigned int: <constructor 0x7ffff1f2f420 type <array_type 0x7ffff1f23498 type <integer_type 0x7ffff1f232a0 T unsigned SI size <integer_cst 0x7ffff202d708 constant 32> unit size <integer_cst 0x7ffff202d410 constant 4> align 32 symtab 0 alias set -1 canonical type 0x7ffff2042540 precision 32 min <integer_cst 0x7ffff202d730 0> max <integer_cst 0x7ffff202d6e0 4294967295> pointer_to_this <pointer_type 0x7ffff1f23540>> SI size <integer_cst 0x7ffff202d708 32> unit size <integer_cst 0x7ffff202d410 4> align 32 symtab 0 alias set -1 canonical type 0x7ffff1f235e8 domain <integer_type 0x7ffff2055690 type <integer_type 0x7ffff2042000 long unsigned int> DI size <integer_cst 0x7ffff202d7d0 constant 64> unit size <integer_cst 0x7ffff202d7f8 constant 8> align 64 symtab 0 alias set -1 canonical type 0x7ffff2055690 precision 64 min <integer_cst 0x7ffff202d438 0> max <integer_cst 0x7ffff202d438 0>>> constant static lngt 1 idx <integer_cst 0x7ffff202db40 type <integer_type 0x7ffff20420a8 bit_size_type> constant 0> val <integer_cst 0x7ffff202d6e0 type <integer_type 0x7ffff2042540 unsigned int> constant 4294967295>> When ccp propagates b[0] into the comparison, the comparison uses T on one side and unsigned int on the other side. When b has T type, ccp doesn't optimize the ... < 4294967295 comparison into ... != 4294967295, while when b has unsigned int type, it does. T's TYPE_MAIN_VARIANT is unsigned int. So, it isn't clear if the middle-end is considering the two types as incompatible or what.
The reassoc issue is caused by http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=159189 BTW, the C++ FE uses T instead of unsigned type for values in the ctor and thus the testcase works there.
Created attachment 21557 [details] gcc46-pr45059.patch Untested fix.
Subject: Bug 45059 Author: jakub Date: Wed Aug 25 09:36:35 2010 New Revision: 163539 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=163539 Log: PR tree-optimization/45059 * tree-ssa-reassoc.c (eliminate_redundant_comparison): Strip useless type conversions from newop{1,2}. Assert t is a comparison and newop{1,2} after the stripping are gimple vals. * gcc.c-torture/compile/pr45059.c: New test. Added: trunk/gcc/testsuite/gcc.c-torture/compile/pr45059.c Modified: trunk/gcc/ChangeLog trunk/gcc/testsuite/ChangeLog trunk/gcc/tree-ssa-reassoc.c
Fixed.