Hello Guix! This patch set aims to hit two bird hunters with one stone: initially my goal was to fix , which has become a hindrance to the use of package transformation options, but it also ends up addressing the fact that those options did not, until now, rewrite implicit dependencies. Concretely, the following commands had no effect thus far: guix build python-itsdangerous --with-input=python=python2 guix build hello --with-input=gcc=gcc-toolchain@10 In both cases, this is because the input we want to change is an implicit input. This patch set fixes that, and it fixes as a side effect. This opens new possibilities. ‘--with-input=python=python2’ is one of them, but ‘--with-input=gcc=gcc-toolchain@10’ is not (it fails to build for obscure reasons that I’ll fix in ‘core-updates’, and it rebuilds the world anyway, which is not practical). Another thing that I find interesting is: $ guix build hello --with-graft=glibc=glibc@2.29 /gnu/store/6jv7icpjbl3pvj24db2q2fmdly9vgp4d-hello-2.10 $ /gnu/store/6jv7icpjbl3pvj24db2q2fmdly9vgp4d-hello-2.10/bin/hello Saluton, mondo! $ LD_TRACE_LOADED_OBJECTS=yes /gnu/store/6jv7icpjbl3pvj24db2q2fmdly9vgp4d-hello-2.10/bin/hello linux-vdso.so.1 (0x00007ffcc87f8000) libgcc_s.so.1 => /gnu/store/1sqr5fa6jbksqmi7hibqaffixy3b1j0y-gcc-7.5.0-lib/lib/libgcc_s.so.1 (0x00007f3f36c3c000) libc.so.6 => /gnu/store/i4iqkjx34r3nmwwblfmkbsbsd3pgapfp-glibc-2.29/lib/libc.so.6 (0x00007f3f36a82000) /gnu/store/i4iqkjx34r3nmwwblfmkbsbsd3pgapfp-glibc-2.29/lib/ld-linux-x86-64.so.2 (0x00007f3f36c57000) It “relinks” the package against a different libc, assuming the ABI is compatible (this particular example downgrades glibc, probably less useful in the real world than upgrading; it works for ‘hello’ but not for ‘inkscape’ due to ABI differences.) Feedback welcome! Ludo’. Ludovic Courtès (4): packages: 'package-mapping' can recurse on implicit inputs. packages: 'package-input-rewriting/spec' can rewrite implicit dependencies. packages: 'package-mapping' correctly recurses into 'replacement'. packages: 'package-input-rewriting' has a #:deep? parameter. doc/guix.texi | 28 ++++---- gnu/packages/guile.scm | 6 +- guix/packages.scm | 153 ++++++++++++++++++++++++++++------------ tests/guix-build.sh | 11 +++ tests/packages.scm | 149 ++++++++++++++++++++++++++++++++++++-- tests/scripts-build.scm | 12 +++- 6 files changed, 291 insertions(+), 68 deletions(-) -- 2.28.0