[llvm-dev] Understanding the version handling in LLVM/Clang/LLD
Sedat Dilek via llvm-dev
llvm-dev at lists.llvm.org
Thu May 21 21:50:11 PDT 2020
On Thu, May 21, 2020 at 4:30 PM Tom Stellard <tstellar at redhat.com> wrote:
>
> On 05/21/2020 03:45 AM, Sedat Dilek wrote:
> > [ Please CC me I ma not subcribed to this mailing-list ]
> >
> > [ CC Tom and Hans as LLVM/stable maintainers ]
> >
> > Hi,
> >
> > I want to understand the version handling in LLVM/Clang/LLD.
> >
> > Normally, I build from "release/10.x" Git branch by using the tool
> > tc-build from ClangBuiltLinux project.
> >
> > With "llvm-10.0.1-rc1" Git tag I was able to setup a llvm-toolchain
> > consisting of the projects "clang" and "lld".
> >
> > A Linux v5.7-rc6 was successfully built.
> >
> > $ cat /proc/version
> > Linux version 5.7.0-rc6-2-amd64-clang (sedat.dilek at gmail.com@iniza)
> > (ClangBuiltLinux clang version 10.0.1
> > (https://github.com/llvm/llvm-project
> > f79cd71e145c6fd005ba4dd1238128dfa0dc2cb6), LLD 10.0.1
> > (https://github.com/llvm/llvm-project
> > f79cd71e145c6fd005ba4dd1238128dfa0dc2cb6)) #2~bullseye+dileks1 SMP
> > 2020-05-20
> >
> > I remember when I used official tarballs for RC releases, the version
> > string should look like:
> >
> > $ clang-10 --version
> > dileks clang version 10.0.1rc1
>
> Are you sure about this? I don't remember rc# being added to version
> strings, do you have an example of an older release build that does this?
>
Hi Tom,
yesterday morning I downloaded llvm-5.0.0rc5.src.tar.xz to check
myself before you answered me:
[ llvm-5.0.0rc5.src/CMakeLists.txt ]
if(NOT DEFINED LLVM_VERSION_MAJOR)
set(LLVM_VERSION_MAJOR 5)
endif()
if(NOT DEFINED LLVM_VERSION_MINOR)
set(LLVM_VERSION_MINOR 0)
endif()
if(NOT DEFINED LLVM_VERSION_PATCH)
set(LLVM_VERSION_PATCH 0)
endif()
if(NOT DEFINED LLVM_VERSION_SUFFIX)
set(LLVM_VERSION_SUFFIX "")
endif()
"I am a bad liar..." (see [1]) or digital dementia :-)?
I have to check my old build-script from my archived Ubuntu/precise
12.04 LTS system.
Darkly I remember I played with some "program-suffix" options.
I will report later.
I will also double check some older binaries from
<https://snapshot.debian.org/> to see if I recall correct and decide
if I need a red or blue pill.
Thanks for taking care!
Regards,
- Sedat -
[1] https://www.youtube.com/watch?v=I-QfPUz1es8
[2] https://snapshot.debian.org/package/llvm-toolchain-3.6/
> -Tom
>
> > Target: x86_64-unknown-linux-gnu
> > Thread model: posix
> > InstalledDir: /home/dileks/src/llvm-toolchain/install/bin
> >
> > $ ld.lld --version
> > LLD 10.0.1rc1 (compatible with GNU linkers)
> >
> > $ llvm-as --version
> > LLVM (http://llvm.org/):
> > LLVM version 10.0.1rc1
> > Optimized build.
> > Default target: x86_64-unknown-linux-gnu
> > Host CPU: sandybridge
> >
> > My first change:
> >
> > [ llvm/CMakeLists.txt ]
> >
> > if(NOT DEFINED LLVM_VERSION_SUFFIX)
> > - set(LLVM_VERSION_SUFFIX "")
> > + set(LLVM_VERSION_SUFFIX "rc1")
> > endif()
> >
> > Unfortunately, clang-10 and ld.lld binaries did not show this in their version.
> >
> > So, I modified clang...
> >
> > [ clang/CMakeLists.txt ]
> >
> > -# Unlike PACKAGE_VERSION, CLANG_VERSION does not include LLVM_VERSION_SUFFIX.
> > -set(CLANG_VERSION
> > "${CLANG_VERSION_MAJOR}.${CLANG_VERSION_MINOR}.${CLANG_VERSION_PATCHLEVEL}")
> > +if(NOT DEFINED CLANG_VERSION_SUFFIX)
> > + set(CLANG_VERSION_SUFFIX ${LLVM_VERSION_SUFFIX})
> > +endif()
> > +# CLANG_VERSION includes LLVM_VERSION_SUFFIX.
> > +set(CLANG_VERSION
> > "${CLANG_VERSION_MAJOR}.${CLANG_VERSION_MINOR}.${CLANG_VERSION_PATCHLEVEL}${CLANG_VERSION_SUFFIX}")
> >
> > ...and lld (the same way clang handles its version):
> >
> > [ lld/CMakeLists.txt ]
> >
> > -# Compute the LLD version from the LLVM version.
> > -string(REGEX MATCH "[0-9]+\\.[0-9]+(\\.[0-9]+)?" LLD_VERSION
> > - ${PACKAGE_VERSION})
> > +# If LLD_VERSION_* is specified, use it, if not use LLVM_VERSION_*.
> > +if(NOT DEFINED LLD_VERSION_MAJOR)
> > + set(LLD_VERSION_MAJOR ${LLVM_VERSION_MAJOR})
> > +endif()
> > +if(NOT DEFINED LLD_VERSION_MINOR)
> > + set(LLD_VERSION_MINOR ${LLVM_VERSION_MINOR})
> > +endif()
> > +if(NOT DEFINED LLD_VERSION_PATCHLEVEL)
> > + set(LLD_VERSION_PATCHLEVEL ${LLVM_VERSION_PATCH})
> > +endif()
> > +if(NOT DEFINED LLD_VERSION_SUFFIX)
> > + set(LLD_VERSION_SUFFIX ${LLVM_VERSION_SUFFIX})
> > +endif()
> > +# LLD_VERSION includes LLVM_VERSION_SUFFIX.
> > +set(LLD_VERSION
> > "${LLD_VERSION_MAJOR}.${LLD_VERSION_MINOR}.${LLD_VERSION_PATCHLEVEL}${LLD_VERSION_SUFFIX}")
> > message(STATUS "LLD version: ${LLD_VERSION}")
> >
> > -string(REGEX REPLACE "([0-9]+)\\.[0-9]+(\\.[0-9]+)?" "\\1" LLD_VERSION_MAJOR
> > - ${LLD_VERSION})
> > -string(REGEX REPLACE "[0-9]+\\.([0-9]+)(\\.[0-9]+)?" "\\1" LLD_VERSION_MINOR
> > - ${LLD_VERSION})
> > -
> >
> > That worked like expected for clang-10 and ld.lld with "-v" and/or
> > "--version" options.
> >
> > A clang-test FAILED... Preprocessor/iwithprefix.c (below when using
> > LLVM_VERSION_SUFFIX = "git"):
> >
> > This is because of the "rc1" string in the include path ("git" accordingly):
> >
> > lib/clang/10.0.1rc1/include
> >
> > To fix this up (maybe someone can help to recognize "git" and "rc[1-9]"):
> >
> > [ clang/test/Preprocessor/iwithprefix.c ]
> >
> > -// CHECK: {{/|\\}}lib{{(32|64)?}}{{/|\\}}clang{{/|\\}}{{[.0-9]+}}{{/|\\}}include
> > +// CHECK: {{/|\\}}lib{{(32|64)?}}{{/|\\}}clang{{/|\\}}{{[.0-9]+}}rc1{{/|\\}}include
> >
> > I guess this is due to my introduction and usage of CLANG_VERSION_SUFFIX.
> >
> > Finally, I looked into master Git where I saw:
> >
> > if(NOT DEFINED LLVM_VERSION_SUFFIX)
> > set(LLVM_VERSION_SUFFIX "git")
> > endif()
> >
> > And re-checked every place where especially...
> > ${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX}
> > ...is used.
> >
> > So, I fixed it up by pre-checking for... if(LLVM_VERSION_SUFFIX STREQUAL "git")
> >
> > Example (full patch attached):
> >
> > [ llvm/cmake/modules/AddLLVM.cmake ]
> >
> > @@ -541,11 +541,18 @@ function(llvm_add_library name)
> > # Set SOVERSION on shared libraries that lack explicit SONAME
> > # specifier, on *nix systems that are not Darwin.
> > if(UNIX AND NOT APPLE AND NOT ARG_SONAME)
> > - set_target_properties(${name}
> > - PROPERTIES
> > - # Since 4.0.0, the ABI version is indicated by the major version
> > - SOVERSION ${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX}
> > - VERSION ${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX})
> > + # Since 4.0.0, the ABI version is indicated by the major version
> > + if(LLVM_VERSION_SUFFIX STREQUAL "git")
> > + set_target_properties(${name}
> > + PROPERTIES
> > + SOVERSION ${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX}
> > + VERSION ${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX})
> > + else()
> > + set_target_properties(${name}
> > + PROPERTIES
> > + SOVERSION ${LLVM_VERSION_MAJOR}
> > + VERSION ${LLVM_VERSION_MAJOR})
> > + endif()
> > endif()
> > endif()
> >
> > @@ -567,8 +574,13 @@ function(llvm_add_library name)
> > if(${output_name} STREQUAL "output_name-NOTFOUND")
> > set(output_name ${name})
> > endif()
> > - set(library_name
> > ${output_name}-${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX})
> > - set(api_name
> > ${output_name}-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.${LLVM_VERSION_PATCH}${LLVM_VERSION_SUFFIX})
> > + if(LLVM_VERSION_SUFFIX STREQUAL "git")
> > + set(library_name
> > ${output_name}-${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX})
> > + set(api_name
> > ${output_name}-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.${LLVM_VERSION_PATCH}${LLVM_VERSION_SUFFIX})
> > + else()
> > + set(library_name ${output_name}-${LLVM_VERSION_MAJOR})
> > + set(api_name
> > ${output_name}-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.${LLVM_VERSION_PATCH})
> > + endif()
> > set_target_properties(${name} PROPERTIES OUTPUT_NAME ${library_name})
> > llvm_install_library_symlink(${api_name} ${library_name} SHARED
> >
> > In the end I was able to build a LLVM/Clang/LLD toolchain which shows
> > me "10.0.1rc1" version string for all llvm-*, clang-10 and ld.lld
> > binaries.
> >
> > As I understand the llvm/stable maintainers do not use or bump
> > LLVM_VERSION_SUFFIX with RC releases as I have expected.
> >
> > But I see some problems when people do not use "git" as value in
> > LLVM_VERSION_SUFFIX - like me "rc1".
> >
> > Also, I see an inconsistency for llvm-* binaries when using "git"
> > whereas Clang and LLD do not show this in their version strings.
> >
> > I am not sure what the introduction of CLANG_VERSION_SUFFIX and
> > LLD_VERSION_SUFFIX is all doing.
> >
> > The only value used for LLVM_VERSION_SUFFIX is "git" in master Git branch.
> >
> > Where is LLVM_VERSION_SUFFIX really relevant?
> > What do you think of the usage of LLVM_VERSION_SUFFIX in general?
> >
> > What do you think to the changes to Clang and LLD versioning?
> >
> > Thanks.
> >
> > Regards,
> > - Sedat -
> >
> > P.S.: Some useful outputs
> >
> > FAIL: Clang :: Preprocessor/iwithprefix.c (8758 of 16586)
> > ******************** TEST 'Clang :: Preprocessor/iwithprefix.c' FAILED
> > ********************
> > Script:
> > --
> > : 'RUN: at line 3'; rm -rf
> > /home/dileks/src/llvm-toolchain/build/stage1/tools/clang/test/Preprocessor/Output/iwithprefix.c.tmp.tmps
> > : 'RUN: at line 4'; mkdir -p
> > /home/dileks/src/llvm-toolchain/build/stage1/tools/clang/test/Preprocessor/Output/iwithprefix.c.tmp.tmps/first
> > /home/dileks/src/llvm-toolchain/build/stage1/tools/clang/test/Preprocessor/Output/iwithprefix.c.tmp.tmps/second
> > : 'RUN: at line 5';
> > /home/dileks/src/llvm-toolchain/build/stage1/bin/clang -cc1
> > -internal-isystem
> > /home/dileks/src/llvm-toolchain/build/stage1/lib/clang/10.0.1git/include
> > -nostdsysteminc -triple x86_64-unknown-unknown -iprefix
> > /home/dileks/src/llvm-toolchain/build/stage1/tools/clang/test/Preprocessor/Output/iwithprefix.c.tmp.tmps/
> > -iwithprefix second -isystem
> > /home/dileks/src/llvm-toolchain/build/stage1/tools/clang/test/Preprocessor/Output/iwithprefix.c.tmp.tmps/first
> > -v /home/dileks/src/llvm-toolchain/tc-build/llvm-project/clang/test/Preprocessor/iwithprefix.c
> > 2> /home/dileks/src/llvm-toolchain/build/stage1/tools/clang/test/Preprocessor/Output/iwithprefix.c.tmp.out
> > : 'RUN: at line 8';
> > /home/dileks/src/llvm-toolchain/build/stage1/bin/FileCheck
> > /home/dileks/src/llvm-toolchain/tc-build/llvm-project/clang/test/Preprocessor/iwithprefix.c
> > < /home/dileks/src/llvm-toolchain/build/stage1/tools/clang/test/Preprocessor/Output/iwithprefix.c.tmp.out
> > --
> > Exit Code: 1
> >
> > Command Output (stderr):
> > --
> > /home/dileks/src/llvm-toolchain/tc-build/llvm-project/clang/test/Preprocessor/iwithprefix.c:12:11:
> > error: CHECK: expected string not found in input
> > // CHECK: {{/|\\}}lib{{(32|64)?}}{{/|\\}}clang{{/|\\}}{{[.0-9]+}}{{/|\\}}include
> > ^
> > <stdin>:6:2: note: scanning from here
> > /home/dileks/src/llvm-toolchain/build/stage1/lib/clang/10.0.1git/include
> > ^
> > <stdin>:6:45: note: possible intended match here
> > /home/dileks/src/llvm-toolchain/build/stage1/lib/clang/10.0.1git/include
> >
> > [ scripts/run_tests_20200520.sh ]
> >
> > #!/bin/sh
> >
> > export LANG=C
> > export LC_ALL=C
> >
> > CLANG_TESTS="Preprocessor/iwithprefix.c"
> >
> > LLVM_LIT_OPTS="--verbose --echo-all-commands --show-all"
> >
> > cd build/stage1/
> >
> > for t in $CLANG_TESTS ; do ./bin/llvm-lit $LLVM_LIT_OPTS
> > ./tools/clang/test/$t ; done
> >
> > - EOT -
> >
>
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