[gentoo-portage-dev] [PATCH] econf: update config.{sub,guess} atomically to avoid races

[gentoo-portage-dev] [PATCH] econf: update config.{sub,guess} atomically to avoid races

[Mike Frysinger]

URL: https://bugs.gentoo.org/487478
---
 bin/phase-helpers.sh | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/bin/phase-helpers.sh b/bin/phase-helpers.sh
index ec48c94..59c053a 100644
--- a/bin/phase-helpers.sh
+++ b/bin/phase-helpers.sh
@@ -512,7 +512,9 @@ econf() {
 			-name config.guess -o -name config.sub ')' -print0 | \
 			while read -r -d $'\0' x ; do
 				__vecho " * econf: updating ${x/${WORKDIR}\/} with ${EPREFIX}/usr/share/gnuconfig/${x##*/}"
-				cp -f "${EPREFIX}"/usr/share/gnuconfig/"${x##*/}" "${x}"
+				# Make sure we do this atomically incase we're run in parallel. #487478
+				cp -f "${EPREFIX}"/usr/share/gnuconfig/"${x##*/}" "${x}.$$"
+				mv -f "${x}.$$" "${x}"
 			done
 		fi
 
-- 
1.8.4.3

[gentoo-portage-dev] [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Mike Frysinger]

Use $BASHPID which will be unique even in subshells.

URL: https://bugs.gentoo.org/487478
---
 bin/phase-helpers.sh | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/bin/phase-helpers.sh b/bin/phase-helpers.sh
index ec48c94..1a7ae03 100644
--- a/bin/phase-helpers.sh
+++ b/bin/phase-helpers.sh
@@ -469,6 +469,7 @@ unpack() {
 
 econf() {
 	local x
+	local pid=${BASHPID}
 
 	if ! ___eapi_has_prefix_variables; then
 		local EPREFIX=
@@ -501,18 +502,22 @@ econf() {
 		if [[ -n $CONFIG_SHELL && \
 			"$(head -n1 "$ECONF_SOURCE/configure")" =~ ^'#!'[[:space:]]*/bin/sh([[:space:]]|$) ]] ; then
 			# preserve timestamp, see bug #440304
-			touch -r "$ECONF_SOURCE/configure" "$ECONF_SOURCE/configure._portage_tmp_.$$" || die
-			sed -e "1s:^#![[:space:]]*/bin/sh:#!$CONFIG_SHELL:" -i "$ECONF_SOURCE/configure" || \
-				die "Substition of shebang in '$ECONF_SOURCE/configure' failed"
-			touch -r "$ECONF_SOURCE/configure._portage_tmp_.$$" "$ECONF_SOURCE/configure" || die
-			rm -f "$ECONF_SOURCE/configure._portage_tmp_.$$"
+			touch -r "${ECONF_SOURCE}/configure" "${ECONF_SOURCE}/configure._portage_tmp_.${pid}" || die
+			sed -i \
+				-e "1s:^#![[:space:]]*/bin/sh:#!$CONFIG_SHELL:" \
+				"${ECONF_SOURCE}/configure" \
+				|| die "Substition of shebang in '${ECONF_SOURCE}/configure' failed"
+			touch -r "${ECONF_SOURCE}/configure._portage_tmp_.${pid}" "${ECONF_SOURCE}/configure" || die
+			rm -f "${ECONF_SOURCE}/configure._portage_tmp_.${pid}"
 		fi
 		if [ -e "${EPREFIX}"/usr/share/gnuconfig/ ]; then
 			find "${WORKDIR}" -type f '(' \
 			-name config.guess -o -name config.sub ')' -print0 | \
 			while read -r -d $'\0' x ; do
 				__vecho " * econf: updating ${x/${WORKDIR}\/} with ${EPREFIX}/usr/share/gnuconfig/${x##*/}"
-				cp -f "${EPREFIX}"/usr/share/gnuconfig/"${x##*/}" "${x}"
+				# Make sure we do this atomically incase we're run in parallel. #487478
+				cp -f "${EPREFIX}"/usr/share/gnuconfig/"${x##*/}" "${x}.${pid}"
+				mv -f "${x}.${pid}" "${x}"
 			done
 		fi
 
-- 
1.8.4.3

Re: [gentoo-portage-dev] [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Brian Dolbec]

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On Tue, 2013-12-17 at 18:28 -0500, Mike Frysinger wrote:
> Use $BASHPID which will be unique even in subshells.
> 
> URL: https://bugs.gentoo.org/487478
> ---
>  bin/phase-helpers.sh | 17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
> 
> diff --git a/bin/phase-helpers.sh b/bin/phase-helpers.sh
> index ec48c94..1a7ae03 100644
> --- a/bin/phase-helpers.sh
> +++ b/bin/phase-helpers.sh
> @@ -469,6 +469,7 @@ unpack() {
>  
>  econf() {
>  	local x
> +	local pid=${BASHPID}
>  
>  	if ! ___eapi_has_prefix_variables; then
>  		local EPREFIX=
> @@ -501,18 +502,22 @@ econf() {
>  		if [[ -n $CONFIG_SHELL && \
>  			"$(head -n1 "$ECONF_SOURCE/configure")" =~ ^'#!'[[:space:]]*/bin/sh([[:space:]]|$) ]] ; then
>  			# preserve timestamp, see bug #440304
> -			touch -r "$ECONF_SOURCE/configure" "$ECONF_SOURCE/configure._portage_tmp_.$$" || die
> -			sed -e "1s:^#![[:space:]]*/bin/sh:#!$CONFIG_SHELL:" -i "$ECONF_SOURCE/configure" || \
> -				die "Substition of shebang in '$ECONF_SOURCE/configure' failed"
> -			touch -r "$ECONF_SOURCE/configure._portage_tmp_.$$" "$ECONF_SOURCE/configure" || die
> -			rm -f "$ECONF_SOURCE/configure._portage_tmp_.$$"
> +			touch -r "${ECONF_SOURCE}/configure" "${ECONF_SOURCE}/configure._portage_tmp_.${pid}" || die
> +			sed -i \
> +				-e "1s:^#![[:space:]]*/bin/sh:#!$CONFIG_SHELL:" \
> +				"${ECONF_SOURCE}/configure" \
> +				|| die "Substition of shebang in '${ECONF_SOURCE}/configure' failed"
> +			touch -r "${ECONF_SOURCE}/configure._portage_tmp_.${pid}" "${ECONF_SOURCE}/configure" || die
> +			rm -f "${ECONF_SOURCE}/configure._portage_tmp_.${pid}"
>  		fi
>  		if [ -e "${EPREFIX}"/usr/share/gnuconfig/ ]; then
>  			find "${WORKDIR}" -type f '(' \
>  			-name config.guess -o -name config.sub ')' -print0 | \
>  			while read -r -d $'\0' x ; do
>  				__vecho " * econf: updating ${x/${WORKDIR}\/} with ${EPREFIX}/usr/share/gnuconfig/${x##*/}"
> -				cp -f "${EPREFIX}"/usr/share/gnuconfig/"${x##*/}" "${x}"
> +				# Make sure we do this atomically incase we're run in parallel. #487478
> +				cp -f "${EPREFIX}"/usr/share/gnuconfig/"${x##*/}" "${x}.${pid}"
> +				mv -f "${x}.${pid}" "${x}"
>  			done
>  		fi
>  


Sorry, my bash skills are not enough to review this stuff. Others will
have to reply :)
-- 
Brian Dolbec <dolsen@gentoo.org>

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Re: [gentoo-portage-dev] [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Alec Warner]

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LGTM


On Tue, Dec 17, 2013 at 4:26 PM, Brian Dolbec <dolsen@gentoo.org> wrote:

> On Tue, 2013-12-17 at 18:28 -0500, Mike Frysinger wrote:
> > Use $BASHPID which will be unique even in subshells.
> >
> > URL: https://bugs.gentoo.org/487478
> > ---
> >  bin/phase-helpers.sh | 17 +++++++++++------
> >  1 file changed, 11 insertions(+), 6 deletions(-)
> >
> > diff --git a/bin/phase-helpers.sh b/bin/phase-helpers.sh
> > index ec48c94..1a7ae03 100644
> > --- a/bin/phase-helpers.sh
> > +++ b/bin/phase-helpers.sh
> > @@ -469,6 +469,7 @@ unpack() {
> >
> >  econf() {
> >       local x
> > +     local pid=${BASHPID}
> >
> >       if ! ___eapi_has_prefix_variables; then
> >               local EPREFIX=
> > @@ -501,18 +502,22 @@ econf() {
> >               if [[ -n $CONFIG_SHELL && \
> >                       "$(head -n1 "$ECONF_SOURCE/configure")" =~
> ^'#!'[[:space:]]*/bin/sh([[:space:]]|$) ]] ; then
> >                       # preserve timestamp, see bug #440304
> > -                     touch -r "$ECONF_SOURCE/configure"
> "$ECONF_SOURCE/configure._portage_tmp_.$$" || die
> > -                     sed -e
> "1s:^#![[:space:]]*/bin/sh:#!$CONFIG_SHELL:" -i "$ECONF_SOURCE/configure"
> || \
> > -                             die "Substition of shebang in
> '$ECONF_SOURCE/configure' failed"
> > -                     touch -r
> "$ECONF_SOURCE/configure._portage_tmp_.$$" "$ECONF_SOURCE/configure" || die
> > -                     rm -f "$ECONF_SOURCE/configure._portage_tmp_.$$"
> > +                     touch -r "${ECONF_SOURCE}/configure"
> "${ECONF_SOURCE}/configure._portage_tmp_.${pid}" || die
> > +                     sed -i \
> > +                             -e
> "1s:^#![[:space:]]*/bin/sh:#!$CONFIG_SHELL:" \
> > +                             "${ECONF_SOURCE}/configure" \
> > +                             || die "Substition of shebang in
> '${ECONF_SOURCE}/configure' failed"
> > +                     touch -r
> "${ECONF_SOURCE}/configure._portage_tmp_.${pid}"
> "${ECONF_SOURCE}/configure" || die
> > +                     rm -f
> "${ECONF_SOURCE}/configure._portage_tmp_.${pid}"
> >               fi
> >               if [ -e "${EPREFIX}"/usr/share/gnuconfig/ ]; then
> >                       find "${WORKDIR}" -type f '(' \
> >                       -name config.guess -o -name config.sub ')' -print0
> | \
> >                       while read -r -d $'\0' x ; do
> >                               __vecho " * econf: updating
> ${x/${WORKDIR}\/} with ${EPREFIX}/usr/share/gnuconfig/${x##*/}"
> > -                             cp -f
> "${EPREFIX}"/usr/share/gnuconfig/"${x##*/}" "${x}"
> > +                             # Make sure we do this atomically incase
> we're run in parallel. #487478
> > +                             cp -f
> "${EPREFIX}"/usr/share/gnuconfig/"${x##*/}" "${x}.${pid}"
> > +                             mv -f "${x}.${pid}" "${x}"
> >                       done
> >               fi
> >
>
>
> Sorry, my bash skills are not enough to review this stuff. Others will
> have to reply :)
> --
> Brian Dolbec <dolsen@gentoo.org>
>

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Re: [gentoo-portage-dev] [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Greg Turner]

On Tue, Dec 17, 2013 at 3:28 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> +                       sed -i \
> +                               -e "1s:^#![[:space:]]*/bin/sh:#!$CONFIG_SHELL:" \
> +                               "${ECONF_SOURCE}/configure" \
> +                               || die "Substition of shebang in '${ECONF_SOURCE}/configure' failed"

Shouldn't we take the same copy, ${pid}-suffix, move approach, here
that we've done with config.{sub,guess}?  Otherwise, what's to stop
these sed's from trampling each other's work-in-progress (the fact
that ebuilds don't crash left and right does suggest that some
mechanism actually does prevent this, already -- but it's a mystery to
me, and I worry it could be some kind of linux-specific filesystem
quirk).

-gmt

Re: [gentoo-portage-dev] [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Alec Warner]

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On Tue, Dec 17, 2013 at 5:41 PM, Greg Turner <gmt@malth.us> wrote:

> On Tue, Dec 17, 2013 at 3:28 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> > +                       sed -i \
> > +                               -e
> "1s:^#![[:space:]]*/bin/sh:#!$CONFIG_SHELL:" \
> > +                               "${ECONF_SOURCE}/configure" \
> > +                               || die "Substition of shebang in
> '${ECONF_SOURCE}/configure' failed"
>
> Shouldn't we take the same copy, ${pid}-suffix, move approach, here
> that we've done with config.{sub,guess}?  Otherwise, what's to stop
> these sed's from trampling each other's work-in-progress (the fact
> that ebuilds don't crash left and right does suggest that some
> mechanism actually does prevent this, already -- but it's a mystery to
> me, and I worry it could be some kind of linux-specific filesystem
> quirk).
>

Sed is already atomic

antarus@goats5 /tmp/test $ cat foo
Debian Rocks!
antarus@goats5 /tmp/test $ strace -e trace=file sed -i -e
's/Debian/Gentoo/g' foo
execve("/bin/sed", ["sed", "-i", "-e", "s/Debian/Gentoo/g", "foo"], [/* 39
vars */]) = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or
directory)
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or
directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or
directory)
open("/lib/x86_64-linux-gnu/libselinux.so.1", O_RDONLY|O_CLOEXEC) = 3
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or
directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or
directory)
open("/lib/x86_64-linux-gnu/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
statfs("/selinux", {f_type="EXT2_SUPER_MAGIC", f_bsize=4096,
f_blocks=5419717, f_bfree=920598, f_bavail=645285, f_files=1379040,
f_ffree=885151, f_fsid={-495840576, 2082046975}, f_namelen=255,
f_frsize=4096}) = 0
open("/proc/filesystems", O_RDONLY)     = 3
open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
open("//lib/charset.alias", O_RDONLY)   = -1 ENOENT (No such file or
directory)
open("/usr/lib/x86_64-linux-gnu/gconv/gconv-modules.cache", O_RDONLY) = 3
open("foo", O_RDONLY)                   = 3
open("/proc/filesystems", O_RDONLY)     = 4
open("./sedfDxBxl", O_RDWR|O_CREAT|O_EXCL, 0600) = 4
rename("./sedfDxBxl", "foo")            = 0

-A


> -gmt
>
>

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Re: [gentoo-portage-dev] [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Greg Turner]

On Tue, Dec 17, 2013 at 5:58 PM, Alec Warner <antarus@gentoo.org> wrote:
> Sed is already atomic
>
> antarus@goats5 /tmp/test $ cat foo
> Debian Rocks!
> antarus@goats5 /tmp/test $ strace -e trace=file sed -i -e
> 's/Debian/Gentoo/g' foo
[snip]
> open("foo", O_RDONLY)                   = 3
> open("/proc/filesystems", O_RDONLY)     = 4
> open("./sedfDxBxl", O_RDWR|O_CREAT|O_EXCL, 0600) = 4
> rename("./sedfDxBxl", "foo")            = 0

Nice demonstration!  Been wondering about that...

-gmt

Re: [gentoo-portage-dev] [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Alec Warner]

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On Tue, Dec 17, 2013 at 6:53 PM, Greg Turner <gmt@malth.us> wrote:

> On Tue, Dec 17, 2013 at 5:58 PM, Alec Warner <antarus@gentoo.org> wrote:
> > Sed is already atomic
> >
> > antarus@goats5 /tmp/test $ cat foo
> > Debian Rocks!
> > antarus@goats5 /tmp/test $ strace -e trace=file sed -i -e
> > 's/Debian/Gentoo/g' foo
> [snip]
> > open("foo", O_RDONLY)                   = 3
> > open("/proc/filesystems", O_RDONLY)     = 4
> > open("./sedfDxBxl", O_RDWR|O_CREAT|O_EXCL, 0600) = 4
> > rename("./sedfDxBxl", "foo")            = 0
>
> Nice demonstration!  Been wondering about that...
>

I originally opened the source code and tried to find the actual rename
code...but gave up after about 2 minutes figuring strace would be quicker.
I was right ;)

-A


>
> -gmt
>
>

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[gentoo-portage-dev] Re: [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Ryan Hill]

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On Tue, 17 Dec 2013 18:28:12 -0500
Mike Frysinger <vapier@gentoo.org> wrote:

> Use $BASHPID which will be unique even in subshells.
> 
> URL: https://bugs.gentoo.org/487478
> ---
>  bin/phase-helpers.sh | 17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
> 
> diff --git a/bin/phase-helpers.sh b/bin/phase-helpers.sh
> index ec48c94..1a7ae03 100644
> --- a/bin/phase-helpers.sh
> +++ b/bin/phase-helpers.sh
> @@ -469,6 +469,7 @@ unpack() {
>  
>  econf() {
>  	local x
> +	local pid=${BASHPID}

This requires bash 4.0.  I'm all for it, but haters gonna hate.


-- 
Ryan Hill                        psn: dirtyepic_sk
   gcc-porting/toolchain/wxwidgets @ gentoo.org

47C3 6D62 4864 0E49 8E9E  7F92 ED38 BD49 957A 8463

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Re: [gentoo-portage-dev] Re: [PATCH] econf: update configure/config.{sub,guess} atomically to avoid races

[Mike Frysinger]

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On Friday 20 December 2013 22:07:17 Ryan Hill wrote:
> On Tue, 17 Dec 2013 18:28:12 -0500 Mike Frysinger wrote:
> > Use $BASHPID which will be unique even in subshells.
> 
> This requires bash 4.0.  I'm all for it, but haters gonna hate.

ugh.  fun fact: this is used in multiple places in portage already, as well as 
some eclasses.

it can be re-implemented with:
	read -r pid _ < /proc/self/stat; echo $pid

but that doesn't work in a subshell, so you couldn't do:
	bashpid() { local pid; read -r pid _ < /proc/self/stat; echo $pid; }
	echo ${BASHPID:-$(bashpid)}
because now you'd be a sub-subshell.  in this case you want the parent pid, 
but that isn't easy to get as the 2nd field of stat is the process name, and 
i'm not sure that won't have spaces (since it might be the name of the shell 
script).  plus it isn't terribly portable.

this seems reasonable portable though:
	bashpid() { sh -c 'echo $PPID'; }
	echo ${BASHPID:-$(bashpid)}
even if it does have the overhead of running another bash process.  but 
considering this only impacts bash-3.2, maybe we simply don't care.
-mike

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[gentoo-portage-dev] [PATCH] add a __bashpid helper for <bash-4.0 versions

[Mike Frysinger]

The $BASHPID variable is new to bash-4.0, so we need to add fallback logic
to support older versions (notably, bash-3.2).

Reported-by: Ryan Hill <dirtyepic@gentoo.org>
---
 bin/ebuild-helpers/prepstrip | 4 ++--
 bin/ebuild.sh                | 2 +-
 bin/helper-functions.sh      | 2 +-
 bin/isolated-functions.sh    | 9 ++++++++-
 bin/phase-functions.sh       | 2 +-
 bin/phase-helpers.sh         | 2 +-
 6 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/bin/ebuild-helpers/prepstrip b/bin/ebuild-helpers/prepstrip
index 9b2d47c..64ea80d 100755
--- a/bin/ebuild-helpers/prepstrip
+++ b/bin/ebuild-helpers/prepstrip
@@ -116,7 +116,7 @@ save_elf_sources() {
 	buildid=$(debugedit -i \
 		-b "${WORKDIR}" \
 		-d "${prepstrip_sources_dir}" \
-		-l "${tmpdir}/sources/${x##*/}.${BASHPID}" \
+		-l "${tmpdir}/sources/${x##*/}.${BASHPID:-$(__bashpid)}" \
 		"${x}")
 }
 
@@ -208,7 +208,7 @@ process_elf() {
 		# see if we can split & strip at the same time
 		if [[ -n ${SPLIT_STRIP_FLAGS} ]] ; then
 			local shortname="${x##*/}.debug"
-			local splitdebug="${tmpdir}/splitdebug/${shortname}.${BASHPID}"
+			local splitdebug="${tmpdir}/splitdebug/${shortname}.${BASHPID:-$(__bashpid)}"
 			${already_stripped} || \
 			${STRIP} ${strip_flags} \
 				-f "${splitdebug}" \
diff --git a/bin/ebuild.sh b/bin/ebuild.sh
index 35f4b91..be044e0 100755
--- a/bin/ebuild.sh
+++ b/bin/ebuild.sh
@@ -468,7 +468,7 @@ if [[ -n ${QA_INTERCEPTORS} ]] ; then
 fi
 
 # Subshell/helper die support (must export for the die helper).
-export EBUILD_MASTER_PID=$BASHPID
+export EBUILD_MASTER_PID=${BASHPID:-$(__bashpid)}
 trap 'exit 1' SIGTERM
 
 if ! has "$EBUILD_PHASE" clean cleanrm depend && \
diff --git a/bin/helper-functions.sh b/bin/helper-functions.sh
index 4a46278..b9bc74a 100644
--- a/bin/helper-functions.sh
+++ b/bin/helper-functions.sh
@@ -34,7 +34,7 @@ __multijob_init() {
 }
 
 __multijob_child_init() {
-	trap 'echo ${BASHPID} $? >&'${mj_write_fd} EXIT
+	trap 'echo ${BASHPID:-$(__bashpid)} $? >&'${mj_write_fd} EXIT
 	trap 'exit 1' INT TERM
 }
 
diff --git a/bin/isolated-functions.sh b/bin/isolated-functions.sh
index 42d9e70..b99aec7 100644
--- a/bin/isolated-functions.sh
+++ b/bin/isolated-functions.sh
@@ -98,6 +98,13 @@ nonfatal() {
 	PORTAGE_NONFATAL=1 "$@"
 }
 
+__bashpid() {
+	# The BASHPID variable is new to bash-4.0, so add a hack for older
+	# versions.  This must be used like so:
+	# ${BASHPID:-$(__bashpid)}
+	sh -c 'echo ${PPID}'
+}
+
 __helpers_die() {
 	if ___eapi_helpers_can_die; then
 		die "$@"
@@ -216,7 +223,7 @@ die() {
 	[[ -n $PORTAGE_IPC_DAEMON ]] && "$PORTAGE_BIN_PATH"/ebuild-ipc exit 1
 
 	# subshell die support
-	[[ $BASHPID = $EBUILD_MASTER_PID ]] || kill -s SIGTERM $EBUILD_MASTER_PID
+	[[ ${BASHPID:-$(__bashpid)} == ${EBUILD_MASTER_PID} ]] || kill -s SIGTERM ${EBUILD_MASTER_PID}
 	exit 1
 }
 
diff --git a/bin/phase-functions.sh b/bin/phase-functions.sh
index 711b721..f39a024 100644
--- a/bin/phase-functions.sh
+++ b/bin/phase-functions.sh
@@ -830,7 +830,7 @@ __ebuild_main() {
 	# setup EBUILD_MASTER_PID to refer to the current $BASHPID,
 	# which seems to give the best results when further
 	# nested subshells call die.
-	export EBUILD_MASTER_PID=$BASHPID
+	export EBUILD_MASTER_PID=${BASHPID:-$(__bashpid)}
 	trap 'exit 1' SIGTERM
 
 	#a reasonable default for $S
diff --git a/bin/phase-helpers.sh b/bin/phase-helpers.sh
index 1a7ae03..412decb 100644
--- a/bin/phase-helpers.sh
+++ b/bin/phase-helpers.sh
@@ -469,7 +469,7 @@ unpack() {
 
 econf() {
 	local x
-	local pid=${BASHPID}
+	local pid=${BASHPID:-$(__bashpid)}
 
 	if ! ___eapi_has_prefix_variables; then
 		local EPREFIX=
-- 
1.8.4.3