| Message ID | 2531b66f78bfdb046ddb.1399375540@argentina |
|---|---|
| State | Superseded |
| Headers | show |
On 06/05/14 13:25, Thomas De Schampheleire wrote: > From: Stefan Sørensen <stefan.sorensen@spectralink.com> > > Currently the check for EABI/EABIhf toolchains looks for the > Tag_ABI_VFP_args attribute in the crt1.o file which gcc adds in an > EABIhf toolchain. > In uClibc, however, crt1.o is not compiled from c but assembly, so the > Tag_ABI_VFP_args attribute is not added in the object file. This causes > the EABIhf check in the external toolchain logic to fail for > uClibc-based toolchains. > > Fix by compiling a dummy .c file and trying to link the object against the > C library. Since it is impossible to mix EABI and EABIhf code, a mismatch > between the buildroot and toolchain ABI settings will be detected during > this link step. > > Fixes bug #6842: https://bugs.busybox.net/show_bug.cgi?id=6842 > > Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com> > [ThomasDS: do full link iso readelf test, update commit message] > Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com> > > --- > v3: (ThomasDS) > - v2 properly recognized a uClibc EABIhf toolchain, but failed to detect a > mismatch with buildroot settings (detected by ThomasP). Fix by > performing an actual link step to detect any incompatibility. > v2: (ThomasDS) > - avoid creating a temporary source file > - update commit message > > toolchain/helpers.mk | 18 ++++++------------ > 1 files changed, 6 insertions(+), 12 deletions(-) > > diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk > --- a/toolchain/helpers.mk > +++ b/toolchain/helpers.mk > @@ -297,20 +297,14 @@ check_arm_abi = \ > echo "External toolchain uses the unsuported OABI" ; \ > exit 1 ; \ > fi ; \ > - EXT_TOOLCHAIN_CRT1=`LANG=C $${__CROSS_CC} -print-file-name=crt1.o` ; \ > - if $${__CROSS_READELF} -A $${EXT_TOOLCHAIN_CRT1} | grep -q "Tag_ABI_VFP_args:" ; then \ > - EXT_TOOLCHAIN_ABI="eabihf" ; \ > - else \ > - EXT_TOOLCHAIN_ABI="eabi" ; \ > - fi ; \ > - if [ "$(BR2_ARM_EABI)" = "y" -a "$${EXT_TOOLCHAIN_ABI}" = "eabihf" ] ; then \ > - echo "Incorrect ABI setting: EABI selected, but toolchain uses EABIhf" ; \ > + TEMP_OBJ_FILE=`mktemp --tmpdir --suffix=.o`; \ > + if ! echo 'int main(void) {}' | $${__CROSS_CC} -x c -o $${TEMP_OBJ_FILE} /dev/null - 2>/dev/null; then \ You can write directly to /dev/null instead of going through TEMP_OBJ_FILE, no? > + abistr_$(BR2_ARM_EABI)='EABI'; \ > + abistr_$(BR2_ARM_EABIHF)='EABIhf'; \ > + echo "Incorrect ABI setting: $${abistr_y} selected, but toolchain is incompatible"; \ Nice approach! But to keep the original output, you could use: $${abistr_y} selected, but toolchain uses $${abistr_} Regards, Arnout > exit 1 ; \ > fi ; \ > - if [ "$(BR2_ARM_EABIHF)" = "y" -a "$${EXT_TOOLCHAIN_ABI}" = "eabi" ] ; then \ > - echo "Incorrect ABI setting: EABIhf selected, but toolchain uses EABI" ; \ > - exit 1 ; \ > - fi > + rm -f $${TEMP_OBJ_FILE} > > # > # Check that the external toolchain supports C++ > _______________________________________________ > buildroot mailing list > buildroot@busybox.net > http://lists.busybox.net/mailman/listinfo/buildroot >
Hi Arnout, On Fri, May 9, 2014 at 12:35 AM, Arnout Vandecappelle <arnout@mind.be> wrote: > On 06/05/14 13:25, Thomas De Schampheleire wrote: >> From: Stefan Sørensen <stefan.sorensen@spectralink.com> >> >> Currently the check for EABI/EABIhf toolchains looks for the >> Tag_ABI_VFP_args attribute in the crt1.o file which gcc adds in an >> EABIhf toolchain. >> In uClibc, however, crt1.o is not compiled from c but assembly, so the >> Tag_ABI_VFP_args attribute is not added in the object file. This causes >> the EABIhf check in the external toolchain logic to fail for >> uClibc-based toolchains. >> >> Fix by compiling a dummy .c file and trying to link the object against the >> C library. Since it is impossible to mix EABI and EABIhf code, a mismatch >> between the buildroot and toolchain ABI settings will be detected during >> this link step. >> >> Fixes bug #6842: https://bugs.busybox.net/show_bug.cgi?id=6842 >> >> Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com> >> [ThomasDS: do full link iso readelf test, update commit message] >> Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com> >> >> --- >> v3: (ThomasDS) >> - v2 properly recognized a uClibc EABIhf toolchain, but failed to detect a >> mismatch with buildroot settings (detected by ThomasP). Fix by >> performing an actual link step to detect any incompatibility. >> v2: (ThomasDS) >> - avoid creating a temporary source file >> - update commit message >> >> toolchain/helpers.mk | 18 ++++++------------ >> 1 files changed, 6 insertions(+), 12 deletions(-) >> >> diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk >> --- a/toolchain/helpers.mk >> +++ b/toolchain/helpers.mk >> @@ -297,20 +297,14 @@ check_arm_abi = \ >> echo "External toolchain uses the unsuported OABI" ; \ >> exit 1 ; \ >> fi ; \ >> - EXT_TOOLCHAIN_CRT1=`LANG=C $${__CROSS_CC} -print-file-name=crt1.o` ; \ >> - if $${__CROSS_READELF} -A $${EXT_TOOLCHAIN_CRT1} | grep -q "Tag_ABI_VFP_args:" ; then \ >> - EXT_TOOLCHAIN_ABI="eabihf" ; \ >> - else \ >> - EXT_TOOLCHAIN_ABI="eabi" ; \ >> - fi ; \ >> - if [ "$(BR2_ARM_EABI)" = "y" -a "$${EXT_TOOLCHAIN_ABI}" = "eabihf" ] ; then \ >> - echo "Incorrect ABI setting: EABI selected, but toolchain uses EABIhf" ; \ >> + TEMP_OBJ_FILE=`mktemp --tmpdir --suffix=.o`; \ >> + if ! echo 'int main(void) {}' | $${__CROSS_CC} -x c -o $${TEMP_OBJ_FILE} /dev/null - 2>/dev/null; then \ > > You can write directly to /dev/null instead of going through TEMP_OBJ_FILE, no? Ah yes. When we were still using the readelf approach I tried avoiding the temporary file by using 'gcc -o -' so that I could pipe it into readelf, but gcc did not accept that. When changing approach I did not realize I could remove it, thanks. I also noticed now that there is an extra /dev/null on this line as input file, which is not needed. > >> + abistr_$(BR2_ARM_EABI)='EABI'; \ >> + abistr_$(BR2_ARM_EABIHF)='EABIhf'; \ >> + echo "Incorrect ABI setting: $${abistr_y} selected, but toolchain is incompatible"; \ > > Nice approach! But to keep the original output, you could use: > > $${abistr_y} selected, but toolchain uses $${abistr_} > This did cross my mind, but it assumes that there are only two possibilities: EABI and EABIhf. Suppose that a new EABI pops up. Or suppose the compilation/link step fails for a completely different reason. Then we have told the user that their toolchain is EABI or EABIhf while it is not true. So here I choice correctness over completeness, but if you prefer I can change it. Do let me know if you still think we should add $${abistr_} to the message. Thanks, Thomas
On 09/05/14 09:23, Thomas De Schampheleire wrote: > Hi Arnout, > > On Fri, May 9, 2014 at 12:35 AM, Arnout Vandecappelle <arnout@mind.be> wrote: >> On 06/05/14 13:25, Thomas De Schampheleire wrote: [snip] >> >>> + abistr_$(BR2_ARM_EABI)='EABI'; \ >>> + abistr_$(BR2_ARM_EABIHF)='EABIhf'; \ >>> + echo "Incorrect ABI setting: $${abistr_y} selected, but toolchain is incompatible"; \ >> >> Nice approach! But to keep the original output, you could use: >> >> $${abistr_y} selected, but toolchain uses $${abistr_} >> > > This did cross my mind, but it assumes that there are only two > possibilities: EABI and EABIhf. Suppose that a new EABI pops up. Or > suppose the compilation/link step fails for a completely different > reason. Then we have told the user that their toolchain is EABI or > EABIhf while it is not true. > So here I choice correctness over completeness, but if you prefer I > can change it. Do let me know if you still think we should add > $${abistr_} to the message. Good point, let's say "incompatible" then. Regards, Arnout
diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk --- a/toolchain/helpers.mk +++ b/toolchain/helpers.mk @@ -297,20 +297,14 @@ check_arm_abi = \ echo "External toolchain uses the unsuported OABI" ; \ exit 1 ; \ fi ; \ - EXT_TOOLCHAIN_CRT1=`LANG=C $${__CROSS_CC} -print-file-name=crt1.o` ; \ - if $${__CROSS_READELF} -A $${EXT_TOOLCHAIN_CRT1} | grep -q "Tag_ABI_VFP_args:" ; then \ - EXT_TOOLCHAIN_ABI="eabihf" ; \ - else \ - EXT_TOOLCHAIN_ABI="eabi" ; \ - fi ; \ - if [ "$(BR2_ARM_EABI)" = "y" -a "$${EXT_TOOLCHAIN_ABI}" = "eabihf" ] ; then \ - echo "Incorrect ABI setting: EABI selected, but toolchain uses EABIhf" ; \ + TEMP_OBJ_FILE=`mktemp --tmpdir --suffix=.o`; \ + if ! echo 'int main(void) {}' | $${__CROSS_CC} -x c -o $${TEMP_OBJ_FILE} /dev/null - 2>/dev/null; then \ + abistr_$(BR2_ARM_EABI)='EABI'; \ + abistr_$(BR2_ARM_EABIHF)='EABIhf'; \ + echo "Incorrect ABI setting: $${abistr_y} selected, but toolchain is incompatible"; \ exit 1 ; \ fi ; \ - if [ "$(BR2_ARM_EABIHF)" = "y" -a "$${EXT_TOOLCHAIN_ABI}" = "eabi" ] ; then \ - echo "Incorrect ABI setting: EABIhf selected, but toolchain uses EABI" ; \ - exit 1 ; \ - fi + rm -f $${TEMP_OBJ_FILE} # # Check that the external toolchain supports C++