> uname -a Linux loanamd25 2.6.16.46-0.10-smp #1 SMP Mon May 7 13:37:05 UTC 2007 x86_64 x86_64 x86_64 GNU/Linux > gfortran --version GNU Fortran (GCC) 4.5.0 > cat f06fkfn.f90 FUNCTION F06FKFN(N,W,INCW,X,INCX) IMPLICIT NONE INTEGER, PARAMETER :: WP = KIND(0.0D0) REAL (KIND=WP) :: F06FKFN REAL (KIND=WP), PARAMETER :: ONE = 1.0E+0_WP REAL (KIND=WP), PARAMETER :: ZERO = 0.0E+0_WP INTEGER, INTENT (IN) :: INCW, INCX, N REAL (KIND=WP), INTENT (IN) :: W(*), X(*) REAL (KIND=WP) :: ABSYI, NORM, SCALE, SSQ INTEGER :: I, IW, IX REAL (KIND=WP), EXTERNAL :: F06BMFN INTRINSIC ABS, SQRT IF (N<1) THEN NORM = ZERO ELSE IF (N==1) THEN NORM = SQRT(W(1))*ABS(X(1)) ELSE IF (INCW>0) THEN IW = 1 ELSE IW = 1 - (N-1)*INCW END IF IF (INCX>0) THEN IX = 1 ELSE IX = 1 - (N-1)*INCX END IF SCALE = ZERO SSQ = ONE DO I = 1, N IF ((W(IW)/=ZERO) .AND. (X(IX)/=ZERO)) THEN ABSYI = SQRT(W(IW))*ABS(X(IX)) IF (SCALE<ABSYI) THEN SSQ = 1 + SSQ*(SCALE/ABSYI)**2 SCALE = ABSYI ELSE SSQ = SSQ + (ABSYI/SCALE)**2 END IF END IF IW = IW + INCW IX = IX + INCX END DO NORM = F06BMFN(SCALE,SSQ) END IF F06FKFN = NORM RETURN END FUNCTION F06FKFN > gfortran -O3 -m32 -fcheck=all -c f06fkfn.f90 f06fkfn.f90: In function ‘f06fkfn’: f06fkfn.f90:1:0: internal compiler error: Segmentation fault
Confirmed on trunk with '-O[23] -m32 -fcheck=bounds' (compiles with '-O[01s]'). Works for me with 4.5 revision 157991 and 4.4.2 (with '-fbounds-check' instead of '-fcheck=bounds'), hence at least a 4.6 regression.
Confirm. It fails with 4.5 and 4.6 using the option -fbounds-check (== -fcheck-bounds), but only with -O2 and higher and for some reasons only with -m32 and not with -m64 on x86_64-unknown-linux-gnu. It works with GCC 4.1/4.2/4.3/4.4. Valgrind shows: ==2634== Invalid read of size 2 ==2634== at 0x9643CA: is_overflow_infinity (tree-vrp.c:184) ==2634== by 0x96447D: usable_range_p (tree-vrp.c:797) ==2634== by 0x96A3DD: compare_ranges (tree-vrp.c:3388) ==2634== by 0x96B083: vrp_evaluate_conditional_warnv_with_ops (tree-vrp.c:5669) ==2634== by 0x96B91F: vrp_evaluate_conditional (tree-vrp.c:5710) ==2634== by 0x9309DE: thread_across_edge (tree-ssa-threadedge.c:537) ==2634== by 0x9765ED: execute_vrp (tree-vrp.c:7214) ==2634== by 0x785B9A: execute_one_pass (passes.c:1569) ==2634== by 0x785E24: execute_pass_list (passes.c:1624) ==2634== by 0x785E36: execute_pass_list (passes.c:1625) ==2634== by 0x87AB34: tree_rest_of_compilation (tree-optimize.c:413) ==2634== by 0x9FCA60: cgraph_expand_function (cgraphunit.c:1548) ==2634== Address 0x0 is not stack'd, malloc'd or (recently) free'd ==2634== test.f90: In function 'f06fkfn': test.f90:1:0: internal compiler error: Segmentation fault Please submit a full bug report,
Program received signal SIGSEGV, Segmentation fault. 0x0000000000bdb380 in needs_overflow_infinity (type=0x0) at /space/rguenther/src/svn/gcc-4_5-branch/gcc/tree-vrp.c:184 184 return INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type); (gdb) up #1 0x0000000000bdb434 in is_overflow_infinity (val=0x7ffff5adfe70) at /space/rguenther/src/svn/gcc-4_5-branch/gcc/tree-vrp.c:269 269 return (needs_overflow_infinity (TREE_TYPE (val)) (gdb) call debug_tree (val) <ssa_name 0x7ffff5adfe70 nothrow var <var_decl 0x7ffff7fbf0a0 i>def_stmt version 56 in-free-list> Confirmed. We free the SSA name in substitute_and_fold () but it is still used in symbolical ranges which we end up using by jump threading. If we do so we shouldn't DCE stmts in substitute_and_fold (). There's also a missed-optimization which if fixed fixes this PR as well.
Subject: Bug 43796 Author: rguenth Date: Mon Apr 19 15:17:26 2010 New Revision: 158520 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=158520 Log: 2010-04-19 Richard Guenther <rguenther@suse.de> PR tree-optimization/43796 * tree-vrp.c (adjust_range_with_scev): Lookup init and step from SCEV in the lattice. (vrp_visit_phi_node): Dump change. * gfortran.dg/pr43796.f90: New testcase. Added: trunk/gcc/testsuite/gfortran.dg/pr43796.f90 Modified: trunk/gcc/ChangeLog trunk/gcc/testsuite/ChangeLog trunk/gcc/tree-vrp.c
Subject: Bug 43796 Author: rguenth Date: Tue Apr 20 09:04:05 2010 New Revision: 158548 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=158548 Log: 2010-04-20 Richard Guenther <rguenther@suse.de> PR tree-optimization/43796 * tree-vrp.c (adjust_range_with_scev): Lookup init and step from SCEV in the lattice. (vrp_visit_phi_node): Dump change. * gfortran.dg/pr43796.f90: New testcase. Added: branches/gcc-4_5-branch/gcc/testsuite/gfortran.dg/pr43796.f90 Modified: branches/gcc-4_5-branch/gcc/ChangeLog branches/gcc-4_5-branch/gcc/testsuite/ChangeLog branches/gcc-4_5-branch/gcc/tree-vrp.c
Fixed.