From 3945d2d77e373c828ebbbb05b3ba06adf39019ab Mon Sep 17 00:00:00 2001 From: Gaius Mulley Date: Tue, 25 Aug 2020 09:39:27 +0100 Subject: [PATCH] gdb/modula-2: parsing of multi-subscript arrays Fix bug PR m2/26372, GDB's inability to parse multi-dimensional modula-2 arrays. We previously had two rules for handling the parsing of array sub-scripts. I have reproduced them here with the actual handler blocks removed to make the bug clearer: exp : exp '[' non_empty_arglist ']' ; exp : exp '[' exp ']' ; non_empty_arglist : exp ; non_empty_arglist : non_empty_arglist ',' exp ; This is ambiguous as the pattern "exp '[' exp" could match either of the 'exp' rules. Currently it just so happens that the parser picks the second 'exp' rule which means we can only handle a single array index. As the handler code for the first 'exp' pattern will correctly handle and number of array indexes then lets just remove the second pattern. gdb/ChangeLog: PR m2/26372 * m2-exp.y (exp): Improve comment for non_empty_arglist case, add an assert. Remove single element array indexing pattern as the MULTI_SUBSCRIPT support will handle this case too. gdb/testsuite/ChangeLog: PR m2/26372 * gdb.modula2/multidim.c: New file. * gdb.modula2/multidim.exp: New file. --- gdb/ChangeLog | 8 ++++++ gdb/m2-exp.y | 13 ++++----- gdb/testsuite/ChangeLog | 6 ++++ gdb/testsuite/gdb.modula2/multidim.c | 39 ++++++++++++++++++++++++++ gdb/testsuite/gdb.modula2/multidim.exp | 37 ++++++++++++++++++++++++ 5 files changed, 96 insertions(+), 7 deletions(-) create mode 100644 gdb/testsuite/gdb.modula2/multidim.c create mode 100644 gdb/testsuite/gdb.modula2/multidim.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 642cb6441b3..4592b84a495 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,11 @@ +2020-08-25 Gaius Mulley + Andrew Burgess + + PR m2/26372 + * m2-exp.y (exp): Improve comment for non_empty_arglist case, add + an assert. Remove single element array indexing pattern as the + MULTI_SUBSCRIPT support will handle this case too. + 2020-08-24 Simon Marchi * value.h (valprint_check_validity): Move declaration from diff --git a/gdb/m2-exp.y b/gdb/m2-exp.y index 70a3d9c483a..c79c1f25828 100644 --- a/gdb/m2-exp.y +++ b/gdb/m2-exp.y @@ -293,21 +293,20 @@ set : '{' arglist '}' ; -/* Modula-2 array subscript notation [a,b,c...] */ +/* Modula-2 array subscript notation [a,b,c...]. */ exp : exp '[' /* This function just saves the number of arguments that follow in the list. It is *not* specific to function types */ { pstate->start_arglist(); } non_empty_arglist ']' %prec DOT - { write_exp_elt_opcode (pstate, MULTI_SUBSCRIPT); + { + gdb_assert (pstate->arglist_len > 0); + write_exp_elt_opcode (pstate, MULTI_SUBSCRIPT); write_exp_elt_longcst (pstate, pstate->end_arglist()); - write_exp_elt_opcode (pstate, MULTI_SUBSCRIPT); } - ; - -exp : exp '[' exp ']' - { write_exp_elt_opcode (pstate, BINOP_SUBSCRIPT); } + write_exp_elt_opcode (pstate, MULTI_SUBSCRIPT); + } ; exp : exp '(' diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index b976a54cc51..f5c258b432c 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2020-08-25 Gaius Mulley + + PR m2/26372 + * gdb.modula2/multidim.c: New file. + * gdb.modula2/multidim.exp: New file. + 2020-08-24 Simon Marchi * lib/gdb.exp (runto): Always emit fail on internal error. diff --git a/gdb/testsuite/gdb.modula2/multidim.c b/gdb/testsuite/gdb.modula2/multidim.c new file mode 100644 index 00000000000..b0ce8488681 --- /dev/null +++ b/gdb/testsuite/gdb.modula2/multidim.c @@ -0,0 +1,39 @@ +/* This test script is part of GDB, the GNU debugger. + + Copyright 2020 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + + +static int a[10][20]; + +static void +here (void) +{ +} + +int +main () +{ + int i, j; + int count = 0; + + for (i = 0; i < 10; i++) + for (j = 0; j < 20; j++) + { + a[i][j] = count; + count += 1; + } + here (); +} diff --git a/gdb/testsuite/gdb.modula2/multidim.exp b/gdb/testsuite/gdb.modula2/multidim.exp new file mode 100644 index 00000000000..ccccaa25981 --- /dev/null +++ b/gdb/testsuite/gdb.modula2/multidim.exp @@ -0,0 +1,37 @@ +# Copyright 2020 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +# This file is part of the gdb testsuite. It contains tests for printing +# the elements of an unbounded array using the Modula-2 language mode of +# gdb. + +standard_testfile multidim.c + +if {[prepare_for_testing "failed to prepare" $testfile $srcfile \ + {debug quiet}]} { + return -1 +} + +if ![runto here] then { + perror "couldn't run to breakpoint 'here'" + continue +} + +gdb_test "set lang modula-2" ".*does not match.*" "switch to modula-2" + +gdb_test "print a\[1,2\]" ".*= 22.*" "second row third column" +gdb_test "print a\[2,1\]" ".*= 41.*" "fifth row second column" +gdb_test "print a\[a\[0,1\],a\[0,2\]\]" ".*= 22.*" \ + "second row third column again" -- 2.30.2