#From vp@dmat.uevora.pt Thu Jun 18 09:10 EDT 1998 #Received: from mescaline.gnu.org (we-refuse-to-spy-on-our-users@mescaline.gnu.org [158.121.106.21]) by cssun.mathcs.emory.edu (8.7.5/8.6.9-940818.01cssun) with ESMTP id JAA23649 for ; Thu, 18 Jun 1998 09:10:54 -0400 (EDT) #Received: from khromeleque.dmat.uevora.pt by mescaline.gnu.org (8.8.5/8.6.12GNU) with ESMTP id JAA21732 for ; Thu, 18 Jun 1998 09:11:19 -0400 #Received: from khromeleque.dmat.uevora.pt (vp@localhost [127.0.0.1]) # by khromeleque.dmat.uevora.pt (8.8.8/8.8.8/Debian/GNU) with ESMTP id OAA11817 # for ; Thu, 18 Jun 1998 14:13:57 +0100 #Message-Id: <199806181313.OAA11817@khromeleque.dmat.uevora.pt> #To: arnold@gnu.org #Subject: concatenation bug in gawk 3.0.3 #Date: Thu, 18 Jun 1998 14:13:57 +0200 #From: Vasco Pedro #Content-Type: text #Content-Length: 2285 #Status: RO # #Hi, # #The gawk program '{print NR " " 10/NR}' will print: # #1 10 #5 5 #3 3.33333 #2 2.5 #2 2 #1 1.66667 # #instead of the correct: # #1 10 #2 5 #3 3.33333 #4 2.5 #5 2 #6 1.66667 # #You'll notice, on the incorrect output, that the first column is #the first digit of the second. # #I think the problem comes from the way builtin variables are handled. #Since the items to be concatenated are processed in reverse order and #the return value of tree_eval(``NR'') is a pointer to the value part #of `NR_node', the `unref()' of `NR_node' due to its second occurrence #will leave a dangling pointer in `strlist'. The reason that it doesn't #reuse the freed space with objects of the same type. (Using Electric #Fence with EF_PROTECT_FREE set confirms that freed space is being #accessed.) # #The enclosed patch (hack would be a better word to describe it) is #all I could come up with. With it installed, things seem to work ok, #but I doubt this is the correct way to do it. (If I treated the #case for `Node_field_spec' as the I did others, `make check' would #fail in several places.) # #Regards, #vasco # #*** eval.c~ Tue May 6 21:39:55 1997 #--- eval.c Thu Jun 18 13:39:25 1998 #*************** #*** 685,697 **** # return func_call(tree->rnode, tree->lnode); # # /* unary operations */ # case Node_NR: # case Node_FNR: # case Node_NF: # case Node_FIELDWIDTHS: # case Node_FS: # case Node_RS: #- case Node_field_spec: # case Node_subscript: # case Node_IGNORECASE: # case Node_OFS: #--- 685,700 ---- # return func_call(tree->rnode, tree->lnode); # # /* unary operations */ #+ case Node_field_spec: #+ lhs = get_lhs(tree, (Func_ptr *) NULL); #+ return *lhs; #+ # case Node_NR: # case Node_FNR: # case Node_NF: # case Node_FIELDWIDTHS: # case Node_FS: # case Node_RS: # case Node_subscript: # case Node_IGNORECASE: # case Node_OFS: #*************** #*** 699,705 **** # case Node_OFMT: # case Node_CONVFMT: # lhs = get_lhs(tree, (Func_ptr *) NULL); #! return *lhs; # # case Node_var_array: # fatal("attempt to use array `%s' in a scalar context", #--- 702,710 ---- # case Node_OFMT: # case Node_CONVFMT: # lhs = get_lhs(tree, (Func_ptr *) NULL); #! r = dupnode(*lhs); #! r->flags |= TEMP; #! return r; # # case Node_var_array: # fatal("attempt to use array `%s' in a scalar context", # { print NR " " 10/NR }