Red Hat Bugzilla – Bug 597848
gdb issues with DW_OP_*piece
Last modified: 2016-09-19 22:06:48 EDT
+++ This bug was initially created as a clone of Bug #589467 +++ Created an attachment (id=411878) sra-1.c On the attached testcase: (gdb) b 20 (gdb) b 31 (gdb) b 42 (gdb) r (gdb) p a $1 = {i = 4, j = 14} (gdb) p a.i $2 = 4 (gdb) p a.j $3 = 4 (gdb) c $3 is wrong, should have been 14. The debug info looks correct and, after all, p a printed it correctly too. (gdb) p a $4 = {4, 14} (gdb) p a[0] Can't take address of "a" which isn't an lvalue. (gdb) p a[1] Can't take address of "a" which isn't an lvalue. (gdb) c When p a is able to print it, so should IMHO p a[0] or p a[1]. (gdb) p a Unhandled dwarf expression opcode 0x9d (gdb) p a.i Unhandled dwarf expression opcode 0x9d (gdb) p a.j Unhandled dwarf expression opcode 0x9d And here DW_OP_bit_piece is unsupported. --- Additional comment from jakub@redhat.com on 2010-05-06 04:55:33 EDT --- This is with http://gcc.gnu.org/PR43983 #c5 patch. --- Additional comment from jakub@redhat.com on 2010-05-06 04:56:23 EDT --- Created an attachment (id=411881) sra-1.s gcc -g -O2 -dA generated x86-64 assembly. --- Additional comment from jakub@redhat.com on 2010-05-06 04:59:26 EDT --- Created an attachment (id=411883) sra-1.s gcc -g -O2 -dA generated x86-64 assembly. --- Additional comment from tromey@redhat.com on 2010-05-21 17:19:33 EDT --- I've checked in 4 patches to upstream gdb that should fix these problems. The unavailable piece patch is not really complete (it warns and fills in zeroes), but it is better than not getting any results at all. --- Additional comment from jan.kratochvil@redhat.com on 2010-05-30 14:19:37 EDT --- gdb-bz589467-pieces1of4.patch = http://sourceware.org/ml/gdb-cvs/2010-05/msg00186.html gdb-bz589467-pieces2of4.patch = http://sourceware.org/ml/gdb-cvs/2010-05/msg00188.html = http://sourceware.org/ml/gdb-cvs/2010-05/msg00189.html gdb-bz589467-pieces3of4.patch = http://sourceware.org/ml/gdb-cvs/2010-05/msg00190.html gdb-bz589467-pieces4of4.patch = http://sourceware.org/ml/gdb-cvs/2010-05/msg00191.html qa_ack: +Running gdb/testsuite/gdb.dwarf2/pieces.exp ... +PASS: gdb.dwarf2/pieces.exp: set f1 breakpoint for pieces +PASS: gdb.dwarf2/pieces.exp: continue to breakpoint: continue to f1 breakpoint for pieces +PASS: gdb.dwarf2/pieces.exp: print a in pieces:f1 +PASS: gdb.dwarf2/pieces.exp: print a.j in pieces:f1 +PASS: gdb.dwarf2/pieces.exp: set f2 breakpoint for pieces +PASS: gdb.dwarf2/pieces.exp: continue to breakpoint: continue to f2 breakpoint for pieces +PASS: gdb.dwarf2/pieces.exp: print a in pieces:f2 +PASS: gdb.dwarf2/pieces.exp: print a[0] in pieces:f2 +PASS: gdb.dwarf2/pieces.exp: print a[1] in pieces:f2 +PASS: gdb.dwarf2/pieces.exp: set f3 breakpoint for pieces +PASS: gdb.dwarf2/pieces.exp: continue to breakpoint: continue to f3 breakpoint for pieces +PASS: gdb.dwarf2/pieces.exp: print a.i in pieces:f3 +PASS: gdb.dwarf2/pieces.exp: print a.j in pieces:f3 +KFAIL: gdb.dwarf2/pieces.exp: set a.i in pieces:f3 (PRMS: no bug yet) +PASS: gdb.dwarf2/pieces.exp: print new a.i in pieces:f3 +PASS: gdb.dwarf2/pieces.exp: set f6 breakpoint for pieces +PASS: gdb.dwarf2/pieces.exp: continue to breakpoint: continue to f6 breakpoint for pieces +PASS: gdb.dwarf2/pieces.exp: print a with optimized out piece +PASS: gdb.dwarf2/pieces.exp: print a.i with optimized out piece
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux major release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Major release. This request is not yet committed for inclusion.
# runtest --tool=gdb gdb.dwarf2/pieces.exp (...) # of expected passes 18 # of known failures 1
Red Hat Enterprise Linux 6.0 is now available and should resolve the problem described in this bug report. This report is therefore being closed with a resolution of CURRENTRELEASE. You may reopen this bug report if the solution does not work for you.