From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by sourceware.org (Postfix) with ESMTPS id 4B961385BF81 for ; Wed, 8 Apr 2020 10:19:16 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 4B961385BF81 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=tdevries@suse.de X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id CB5E3AF26; Wed, 8 Apr 2020 10:19:14 +0000 (UTC) Date: Wed, 8 Apr 2020 12:19:13 +0200 From: Tom de Vries To: gdb-patches@sourceware.org Cc: Tom Tromey Subject: [PATCH][gdb/symtab] Don't create duplicate psymtab for forward-imported CU Message-ID: <20200408101912.GA32538@delia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) X-Spam-Status: No, score=-31.2 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_DMARC_STATUS, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Apr 2020 10:19:17 -0000 Hi, Consider the executable generated for test-case gdb.dwarf2/imported-unit.exp. When loading the executable using various tracing: ... $ gdb \ outputs/gdb.dwarf2/imported-unit/imported-unit \ -batch \ -iex "set verbose on" \ -iex "set debug symtab-create 1" ... Created psymtab 0x213f380 for module @0xc7. Created psymtab 0x20e7b00 for module imported_unit.c. Created psymtab 0x215da20 for module imported_unit.c. Created psymtab 0x2133630 for module elf-init.c. Created psymtab 0x215b910 for module ../sysdeps/x86_64/crtn.S. ... we notice that there are two psymtabs generated for imported_unit.c. This is due to the following: in dwarf2_build_psymtabs_hard we loop over CUs and generate partial symtabs for those, and if we encounter an import of another CU, we also generate a partial symtab for that one, unless already created. This works well with backward import references: - the imported CU is read - then the importing CU is read - the import is encountered, but the imported CU is already read, so we're done. But with forward import references, we have instead: - the importing CU is read - the import is encountered, and the imported CU is read - the imported CU is read once more Fix this by skipping already created psymtabs in the loop in dwarf2_build_psymtabs_hard. Build in combination with the tentative fix for PR25718 - "[ada] symbol in imported unit not found" ( https://sourceware.org/pipermail/gdb-patches/2020-March/167152.html ) to prevent this regression: ... FAIL: gdb.ada/char_enum.exp: ptype pck.Global_Enum_Type ... Tested on x86_64-linux, with native and target board unix/-flto/-O0/-flto-partition=none/-ffat-lto-objects. This causes this regression with the target board: ... FAIL: gdb.ada/dgopt.exp: list x.adb:16, 16 ... which I consider a seperate PR, filed as PR25801 - "Filename of shared psymtab is ignored". OK for trunk? Thanks, - Tom [gdb/symtab] Don't create duplicate psymtab for forward-imported CU gdb/ChangeLog: 2020-04-08 Tom de Vries PR symtab/25700 * dwarf2/read.c (dwarf2_build_psymtabs_hard): Don't create psymtab for CU if already created. gdb/testsuite/ChangeLog: 2020-04-08 Tom de Vries PR symtab/25700 * gdb.dwarf2/imported-unit.exp: Verify that there's only one partial symtab for imported_unit.c. --- gdb/dwarf2/read.c | 7 ++++++- gdb/testsuite/gdb.dwarf2/imported-unit.exp | 18 ++++++++++++++++++ 2 files changed, 24 insertions(+), 1 deletion(-) diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c index c0b5e58b17..8b761e891e 100644 --- a/gdb/dwarf2/read.c +++ b/gdb/dwarf2/read.c @@ -7781,7 +7781,12 @@ dwarf2_build_psymtabs_hard (struct dwarf2_per_objfile *dwarf2_per_objfile) addrmap_create_mutable (&temp_obstack)); for (dwarf2_per_cu_data *per_cu : dwarf2_per_objfile->all_comp_units) - process_psymtab_comp_unit (per_cu, false, language_minimal); + { + if (per_cu->v.psymtab != NULL) + /* In case a forward DW_TAG_imported_unit has read the CU already. */ + continue; + process_psymtab_comp_unit (per_cu, false, language_minimal); + } /* This has to wait until we read the CUs, we need the list of DWOs. */ process_skeletonless_type_units (dwarf2_per_objfile); diff --git a/gdb/testsuite/gdb.dwarf2/imported-unit.exp b/gdb/testsuite/gdb.dwarf2/imported-unit.exp index 41a7505459..d7b3d4c539 100644 --- a/gdb/testsuite/gdb.dwarf2/imported-unit.exp +++ b/gdb/testsuite/gdb.dwarf2/imported-unit.exp @@ -168,6 +168,24 @@ if { $psymtabs_p } { } else { unsupported $test } + +# Verify that there's only one partial symtab for imported_unit.c. Test-case +# for PR25700. +set test "no duplicate psymtab for imported_unit.c" +if { $psymtabs_p } { + set line "Partial symtab for source file imported_unit.c" + gdb_test_multiple "maint print psymbols" $test { + -re -wrap "$line.*$line.*" { + fail $gdb_test_name + } + -re -wrap "$line.*" { + pass $gdb_test_name + } + } +} else { + unsupported $test +} + # Sanity check gdb_test "ptype main" "= int \\(void\\)"