Re: [PATCH] build: Check for cargo when building rust language

[Arthur Cohen <arthur.cohen@embecosm.com>]

Hi Andrew,

On 4/9/24 16:12, Andrew Pinski wrote:
> On Mon, Apr 8, 2024 at 9:39 AM <pierre-emmanuel.patry@embecosm.com> wrote:
>>
>> From: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
>>
>> Hello,
>>
>> The rust frontend requires cargo to build some of it's components,
>> it's presence was not checked during configuration.
> 
> NOTE cargo itself is a huge security hole. If anything we should place
> all of the required dependencies with the specific versions that has
> been tested on gcc.gnu.org (with md5 sums) and download that instead
> of depending on some random downloads via cargo. Talk about broken
> supply chain when things are downloading things randomly off the
> internet.

There is no need to download things randomly off the internet in order 
to work with cargo. We have a commit being reviewed which vendors our 
format parser's two dependencies (libc and unicode functions), and makes 
it so that cargo builds our components with the --offline flag for no 
internet access. This will be upstreamed soon.

This was a simple one line command and it has been tested on containers 
without internet access.

> 
> If there is a way to cache and use those specific versions using
> cargo, that should be done but I suspect cargo does not work that way.

As we talked about yesterday on IRC, cargo does work that way. Sorry if 
I was unclear.

> Also any time someone says this is a temporary measure it is NOT and
> we should never treat it as such unless you already have a patch to
> remove it.

When the time comes we will be more than happy to remove our dependency 
on rustc in order to compiler our dependencies with our own Rust 
front-end. It is one of my objectives, and we're working hard towards 
making that possible :)

Respectfully,

Arthur

> 
> 
> Thanks,
> Andrew Pinski
> 
> 
>>
>> Best regards,
>> Pierre-Emmanuel
>>
>> ----------
>>
>> Prevent rust language from building when cargo is
>> missing.
>>
>> config/ChangeLog:
>>
>>          * acx.m4: Add a macro to check for rust
>>          components.
>>
>> ChangeLog:
>>
>>          * configure: Regenerate.
>>          * configure.ac: Emit an error message when cargo
>>          is missing.
>>
>> Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
>> ---
>>   config/acx.m4 |  11 +++++
>>   configure     | 117 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>   configure.ac  |  18 ++++++++
>>   3 files changed, 146 insertions(+)
>>
>> diff --git a/config/acx.m4 b/config/acx.m4
>> index 7efe98aaf96..3c5fe67342e 100644
>> --- a/config/acx.m4
>> +++ b/config/acx.m4
>> @@ -424,6 +424,17 @@ else
>>   fi
>>   ])
>>
>> +# Test for Rust
>> +# We require cargo and rustc for some parts of the rust compiler.
>> +AC_DEFUN([ACX_PROG_CARGO],
>> +[AC_REQUIRE([AC_CHECK_TOOL_PREFIX])
>> +AC_CHECK_TOOL(CARGO, cargo, no)
>> +if test "x$CARGO" != xno; then
>> +  have_cargo=yes
>> +else
>> +  have_cargo=no
>> +fi])
>> +
>>   # Test for D.
>>   AC_DEFUN([ACX_PROG_GDC],
>>   [AC_REQUIRE([AC_CHECK_TOOL_PREFIX])
>> diff --git a/configure b/configure
>> index 874966fb9f0..46e66e20197 100755
>> --- a/configure
>> +++ b/configure
>> @@ -714,6 +714,7 @@ PGO_BUILD_GEN_CFLAGS
>>   HAVE_CXX11_FOR_BUILD
>>   HAVE_CXX11
>>   do_compare
>> +CARGO
>>   GDC
>>   GNATMAKE
>>   GNATBIND
>> @@ -5786,6 +5787,104 @@ else
>>     have_gdc=no
>>   fi
>>
>> +
>> +if test -n "$ac_tool_prefix"; then
>> +  # Extract the first word of "${ac_tool_prefix}cargo", so it can be a program name with args.
>> +set dummy ${ac_tool_prefix}cargo; ac_word=$2
>> +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
>> +$as_echo_n "checking for $ac_word... " >&6; }
>> +if ${ac_cv_prog_CARGO+:} false; then :
>> +  $as_echo_n "(cached) " >&6
>> +else
>> +  if test -n "$CARGO"; then
>> +  ac_cv_prog_CARGO="$CARGO" # Let the user override the test.
>> +else
>> +as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
>> +for as_dir in $PATH
>> +do
>> +  IFS=$as_save_IFS
>> +  test -z "$as_dir" && as_dir=.
>> +    for ac_exec_ext in '' $ac_executable_extensions; do
>> +  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
>> +    ac_cv_prog_CARGO="${ac_tool_prefix}cargo"
>> +    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
>> +    break 2
>> +  fi
>> +done
>> +  done
>> +IFS=$as_save_IFS
>> +
>> +fi
>> +fi
>> +CARGO=$ac_cv_prog_CARGO
>> +if test -n "$CARGO"; then
>> +  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CARGO" >&5
>> +$as_echo "$CARGO" >&6; }
>> +else
>> +  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
>> +$as_echo "no" >&6; }
>> +fi
>> +
>> +
>> +fi
>> +if test -z "$ac_cv_prog_CARGO"; then
>> +  ac_ct_CARGO=$CARGO
>> +  # Extract the first word of "cargo", so it can be a program name with args.
>> +set dummy cargo; ac_word=$2
>> +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
>> +$as_echo_n "checking for $ac_word... " >&6; }
>> +if ${ac_cv_prog_ac_ct_CARGO+:} false; then :
>> +  $as_echo_n "(cached) " >&6
>> +else
>> +  if test -n "$ac_ct_CARGO"; then
>> +  ac_cv_prog_ac_ct_CARGO="$ac_ct_CARGO" # Let the user override the test.
>> +else
>> +as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
>> +for as_dir in $PATH
>> +do
>> +  IFS=$as_save_IFS
>> +  test -z "$as_dir" && as_dir=.
>> +    for ac_exec_ext in '' $ac_executable_extensions; do
>> +  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
>> +    ac_cv_prog_ac_ct_CARGO="cargo"
>> +    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
>> +    break 2
>> +  fi
>> +done
>> +  done
>> +IFS=$as_save_IFS
>> +
>> +fi
>> +fi
>> +ac_ct_CARGO=$ac_cv_prog_ac_ct_CARGO
>> +if test -n "$ac_ct_CARGO"; then
>> +  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CARGO" >&5
>> +$as_echo "$ac_ct_CARGO" >&6; }
>> +else
>> +  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
>> +$as_echo "no" >&6; }
>> +fi
>> +
>> +  if test "x$ac_ct_CARGO" = x; then
>> +    CARGO="no"
>> +  else
>> +    case $cross_compiling:$ac_tool_warned in
>> +yes:)
>> +{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
>> +$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
>> +ac_tool_warned=yes ;;
>> +esac
>> +    CARGO=$ac_ct_CARGO
>> +  fi
>> +else
>> +  CARGO="$ac_cv_prog_CARGO"
>> +fi
>> +
>> +if test "x$CARGO" != xno; then
>> +  have_cargo=yes
>> +else
>> +  have_cargo=no
>> +fi
>>   { $as_echo "$as_me:${as_lineno-$LINENO}: checking how to compare bootstrapped objects" >&5
>>   $as_echo_n "checking how to compare bootstrapped objects... " >&6; }
>>   if ${gcc_cv_prog_cmp_skip+:} false; then :
>> @@ -9099,6 +9198,24 @@ $as_echo "$as_me: WARNING: --enable-host-shared required to build $language" >&2
>>             ;;
>>           esac
>>
>> +        # Disable Rust if cargo is unavailable.
>> +        case ${add_this_lang}:${language}:${have_cargo} in
>> +          yes:rust:no)
>> +            # Specifically requested language; tell them.
>> +            as_fn_error $? "cargo is required to build $language" "$LINENO" 5
>> +            ;;
>> +          all:rust:no)
>> +            { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: cargo is required to build $language" >&5
>> +$as_echo "$as_me: WARNING: cargo is required to build $language" >&2;}
>> +            add_this_lang=unsupported
>> +            ;;
>> +          *:rust:no)
>> +            # Silently disable.
>> +            add_this_lang=unsupported
>> +            ;;
>> +        esac
>> +
>> +
>>           # Disable a language that is unsupported by the target.
>>          case "${add_this_lang}: $unsupported_languages " in
>>            no:*) ;;
>> diff --git a/configure.ac b/configure.ac
>> index 4f34004a072..8c33c89d02c 100644
>> --- a/configure.ac
>> +++ b/configure.ac
>> @@ -1411,6 +1411,7 @@ fi
>>
>>   ACX_PROG_GNAT
>>   ACX_PROG_GDC
>> +ACX_PROG_CARGO
>>   ACX_PROG_CMP_IGNORE_INITIAL
>>
>>   AC_ARG_ENABLE([bootstrap],
>> @@ -2305,6 +2306,23 @@ directories, to avoid imposing the performance cost of
>>             ;;
>>           esac
>>
>> +        # Disable Rust if cargo is unavailable.
>> +        case ${add_this_lang}:${language}:${have_cargo} in
>> +          yes:rust:no)
>> +            # Specifically requested language; tell them.
>> +            AC_MSG_ERROR([cargo is required to build $language])
>> +            ;;
>> +          all:rust:no)
>> +            AC_MSG_WARN([cargo is required to build $language])
>> +            add_this_lang=unsupported
>> +            ;;
>> +          *:rust:no)
>> +            # Silently disable.
>> +            add_this_lang=unsupported
>> +            ;;
>> +        esac
>> +
>> +
>>           # Disable a language that is unsupported by the target.
>>          case "${add_this_lang}: $unsupported_languages " in
>>            no:*) ;;
>> --
>> 2.43.0
>>