From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2140) id 4C6123835749; Wed, 22 Jun 2022 05:22:14 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 4C6123835749 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Alexandre Oliva To: gcc-cvs@gcc.gnu.org Subject: [gcc(refs/users/aoliva/heads/testme)] Introduce -nolibstdc++ option X-Act-Checkin: gcc X-Git-Author: Alexandre Oliva X-Git-Refname: refs/users/aoliva/heads/testme X-Git-Oldrev: 98b6e62cf5e7d477b5797084da59561f6d018668 X-Git-Newrev: 766d5eb1939df3bbc4dc1c407a1b6e56039ae4fb Message-Id: <20220622052214.4C6123835749@sourceware.org> Date: Wed, 22 Jun 2022 05:22:14 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 Jun 2022 05:22:14 -0000 https://gcc.gnu.org/g:766d5eb1939df3bbc4dc1c407a1b6e56039ae4fb commit 766d5eb1939df3bbc4dc1c407a1b6e56039ae4fb Author: Alexandre Oliva Date: Mon Jun 20 19:44:23 2022 -0300 Introduce -nolibstdc++ option Using g++ to link without libstdc++, as in g++.dg/abi/pure-virtual1.C, is error prone, because there's no way to tell g++ to drop libstdc++ without also dropping libc and any other libraries that the target implicitly links in. This has often led to the need for manual adjustments to this testcase. I figured adding support for -nolibstdc++, even though redundant, makes some sense. One could presumably use gcc rather than g++ for linking, for the same effect, but sometimes changing the link command is harder than adding an option, as in our testsuite. for gcc/ChangeLog * common.opt (nolibstdc++): New. * doc/invoke.texi (-nolibstdc++): Document it. for gcc/cp/ChangeLog * g++spec.c (lang_specific_driver): Implement -nolibstdc++. for gcc/testsuite/ChangeLog * g++.dg/abi/pure-virtual1.C: Use -nolibstdc++. Diff: --- gcc/common.opt | 3 +++ gcc/cp/g++spec.cc | 1 + gcc/doc/invoke.texi | 6 +++++- gcc/testsuite/g++.dg/abi/pure-virtual1.C | 2 +- 4 files changed, 10 insertions(+), 2 deletions(-) diff --git a/gcc/common.opt b/gcc/common.opt index 32917aafcae..e00c6fc2fb0 100644 --- a/gcc/common.opt +++ b/gcc/common.opt @@ -3456,6 +3456,9 @@ Driver nolibc Driver +nolibstdc++ +Driver + nostdlib Driver diff --git a/gcc/cp/g++spec.cc b/gcc/cp/g++spec.cc index 8174d652776..539e6ca089d 100644 --- a/gcc/cp/g++spec.cc +++ b/gcc/cp/g++spec.cc @@ -160,6 +160,7 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, { case OPT_nostdlib: case OPT_nodefaultlibs: + case OPT_nolibstdc__: library = -1; break; diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index fb506364702..de105ddf029 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -652,7 +652,7 @@ Objective-C and Objective-C++ Dialects}. @item Linker Options @xref{Link Options,,Options for Linking}. @gccoptlist{@var{object-file-name} -fuse-ld=@var{linker} -l@var{library} @gol --nostartfiles -nodefaultlibs -nolibc -nostdlib @gol +-nostartfiles -nodefaultlibs -nolibc -nolibstdc++ -nostdlib @gol -e @var{entry} --entry=@var{entry} @gol -pie -pthread -r -rdynamic @gol -s -static -static-pie -static-libgcc -static-libstdc++ @gol @@ -16787,6 +16787,10 @@ absence of a C library is assumed, for example @option{-lpthread} or @option{-lm} in some configurations. This is intended for bare-board targets when there is indeed no C library available. +@item -nolibstdc++ +@opindex nolibstdc++ +Do not link with standard C++ libraries implicitly. + @item -nostdlib @opindex nostdlib Do not use the standard system startup files or libraries when linking. diff --git a/gcc/testsuite/g++.dg/abi/pure-virtual1.C b/gcc/testsuite/g++.dg/abi/pure-virtual1.C index 538e2cb097a..889c33e4952 100644 --- a/gcc/testsuite/g++.dg/abi/pure-virtual1.C +++ b/gcc/testsuite/g++.dg/abi/pure-virtual1.C @@ -1,7 +1,7 @@ // Test that we don't need libsupc++ just for __cxa_pure_virtual. // { dg-do link } // { dg-require-weak } -// { dg-additional-options "-fno-rtti -nodefaultlibs -lc" } +// { dg-additional-options "-fno-rtti -nolibstdc++" } // { dg-additional-options "-Wl,-undefined,dynamic_lookup" { target *-*-darwin* } } // { dg-xfail-if "AIX weak" { powerpc-ibm-aix* } }