From 9ba202c78f0aa39f49929eee63c367847da72ee4 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Fri, 14 Jan 2022 20:16:05 +0100 Subject: [PATCH] Add --with-rtld-early-cflags configure option Reviewed-by: H.J. Lu Reviewed-by: Carlos O'Donell --- INSTALL | 8 ++++++++ NEWS | 6 ++++++ config.make.in | 1 + configure | 13 +++++++++++++ configure.ac | 6 ++++++ elf/Makefile | 8 ++++++++ manual/install.texi | 7 +++++++ 7 files changed, 49 insertions(+) diff --git a/INSTALL b/INSTALL index 331d405e56..a9dc12fa31 100644 --- a/INSTALL +++ b/INSTALL @@ -106,6 +106,14 @@ if 'CFLAGS' is specified it must enable optimization. For example: particular case and potentially change debugging information and metadata only). +'--with-rtld-early-cflags=CFLAGS' + Use additional compiler flags CFLAGS to build the early startup + code of the dynamic linker. These flags can be used to enable + early dynamic linker diagnostics to run on CPUs which are not + compatible with the rest of the GNU C Library, for example, due to + compiler flags which target a later instruction set architecture + (ISA). + '--with-timeoutfactor=NUM' Specify an integer NUM to scale the timeout of test programs. This factor can be changed at run time using 'TIMEOUTFACTOR' environment diff --git a/NEWS b/NEWS index a957b19fdc..ddd95a8329 100644 --- a/NEWS +++ b/NEWS @@ -120,6 +120,12 @@ Major new features: The OpenRISC ABI is 32-bit big-endian and uses 64-bit time (y2038 safe) and 64-bit file offsets (LFS default). +* A new configure option, --with-rtld-early-cflags, can be used to + specify additional compiler flags for building the early startup code + of the dynamic linker. On targets which have CPU compatibility + checks, this can help to ensure that proper diagnostics are printed if + the dynamic loader runs on an incompatible CPU. + Deprecated and removed features, and other changes affecting compatibility: * On x86-64, the LD_PREFER_MAP_32BIT_EXEC environment variable support diff --git a/config.make.in b/config.make.in index e8630a8d0c..6d43e691f7 100644 --- a/config.make.in +++ b/config.make.in @@ -110,6 +110,7 @@ CFLAGS = @CFLAGS@ CPPFLAGS-config = @CPPFLAGS@ CPPUNDEFS = @CPPUNDEFS@ extra-nonshared-cflags = @extra_nonshared_cflags@ +rtld-early-cflags = @rtld_early_cflags@ ASFLAGS-config = @ASFLAGS_config@ AR = @AR@ NM = @NM@ diff --git a/configure b/configure index 3f956cf777..6a7e5c6164 100755 --- a/configure +++ b/configure @@ -681,6 +681,7 @@ force_install bindnow hardcoded_path_in_tests enable_timezone_tools +rtld_early_cflags extra_nonshared_cflags use_default_link sysheaders @@ -761,6 +762,7 @@ with_selinux with_headers with_default_link with_nonshared_cflags +with_rtld_early_cflags with_timeoutfactor enable_sanity_checks enable_shared @@ -1480,6 +1482,8 @@ Optional Packages: --with-default-link do not use explicit linker scripts --with-nonshared-cflags=CFLAGS build nonshared libraries with additional CFLAGS + --with-rtld-early-cflags=CFLAGS + build early initialization with additional CFLAGS --with-timeoutfactor=NUM specify an integer to scale the timeout --with-cpu=CPU select code for CPU variant @@ -3386,6 +3390,15 @@ fi +# Check whether --with-rtld-early-cflags was given. +if test "${with_rtld_early_cflags+set}" = set; then : + withval=$with_rtld_early_cflags; rtld_early_cflags=$withval +else + rtld_early_cflags= +fi + + + # Check whether --with-timeoutfactor was given. if test "${with_timeoutfactor+set}" = set; then : diff --git a/configure.ac b/configure.ac index 277d3527d2..40f2de1661 100644 --- a/configure.ac +++ b/configure.ac @@ -162,6 +162,12 @@ AC_ARG_WITH([nonshared-cflags], [extra_nonshared_cflags=$withval], [extra_nonshared_cflags=]) AC_SUBST(extra_nonshared_cflags) +AC_ARG_WITH([rtld-early-cflags], + AS_HELP_STRING([--with-rtld-early-cflags=CFLAGS], + [build early initialization with additional CFLAGS]), + [rtld_early_cflags=$withval], + [rtld_early_cflags=]) +AC_SUBST(rtld_early_cflags) AC_ARG_WITH([timeoutfactor], AS_HELP_STRING([--with-timeoutfactor=NUM], diff --git a/elf/Makefile b/elf/Makefile index 3df49742ff..e6a28b243b 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -167,6 +167,14 @@ CFLAGS-.o += $(call elide-stack-protector,.o,$(elide-routines.os)) CFLAGS-.op += $(call elide-stack-protector,.op,$(elide-routines.os)) CFLAGS-.os += $(call elide-stack-protector,.os,$(all-rtld-routines)) +# Add the requested compiler flags to the early startup code. +CFLAGS-dl-printf.os += $(rtld-early-cflags) +CFLAGS-dl-sysdep.os += $(rtld-early-cflags) +CFLAGS-dl-tunables.os += $(rtld-early-cflags) +CFLAGS-dl-write.os += $(rtld-early-cflags) +CFLAGS-dl-writev.os += $(rtld-early-cflags) +CFLAGS-rtld.os += $(rtld-early-cflags) + ifeq ($(unwind-find-fde),yes) routines += unwind-dw2-fde-glibc shared-only-routines += unwind-dw2-fde-glibc diff --git a/manual/install.texi b/manual/install.texi index b1afc56f5a..accaef45fa 100644 --- a/manual/install.texi +++ b/manual/install.texi @@ -131,6 +131,13 @@ that the objects in @file{libc_nonshared.a} are compiled with this flag (although this will not affect the generated code in this particular case and potentially change debugging information and metadata only). +@item --with-rtld-early-cflags=@var{cflags} +Use additional compiler flags @var{cflags} to build the early startup +code of the dynamic linker. These flags can be used to enable early +dynamic linker diagnostics to run on CPUs which are not compatible with +the rest of @theglibc{}, for example, due to compiler flags which target +a later instruction set architecture (ISA). + @item --with-timeoutfactor=@var{NUM} Specify an integer @var{NUM} to scale the timeout of test programs. This factor can be changed at run time using @env{TIMEOUTFACTOR}