Subject: Re: [PATCH] build: haskell-build-system: Support packages w. multiple libraries

From: itd <[email-masked]>
Date: Fri, 23 Sep 2022 11:42:41 +0200

Hi,

thanks for the patch!  I applied it, tried it, and ran into some build
issues.  Maybe I missed something; here is (roughly) what I tried:

$ # apply diff to current master
$ git checkout a57c4eff6bbdcff79294fa15ecb95ab2b3c55bb4
$ git checkout origin/wip-haskell -- guix/build/haskell-build-system.scm
$ # bump ghc-attoparsec version
$ git diff gnu/packages/haskell-xyz.scm
diff --git a/gnu/packages/haskell-xyz.scm b/gnu/packages/haskell-xyz.scm
index db653f8c93..c4da66aa4a 100644
--- a/gnu/packages/haskell-xyz.scm
+++ b/gnu/packages/haskell-xyz.scm
@@ -589,7 +589,7 @@ (define-public ghc-atomic-write-0.2.0.7
 (define-public ghc-attoparsec
   (package
     (name "ghc-attoparsec")
-    (version "0.13.2.5")
+    (version "0.14.4")
     (source
      (origin
        (method url-fetch)
@@ -599,10 +599,12 @@ (define-public ghc-attoparsec
              ".tar.gz"))
        (sha256
         (base32
-         "0vv88m5m7ynjrg114psp4j4s69f1a5va3bvn293vymqrma7g7q11"))))
+         "0v4yjz4qi8bwhbyavqxlhsfb1iv07v10gxi64khmsmi4hvjpycrz"))))
     (build-system haskell-build-system)
     (arguments
-     `(#:phases
+     `(#:cabal-revision
+       ("2" "00jyrn2asz1kp698l3fyh19xxxz4npf1993y041x9b9cq239smn0")
+       #:phases
        (modify-phases %standard-phases
          (add-after 'unpack 'patch-for-newer-quickcheck
            (lambda _
$ # build ghc-attoparsec-iso8601 which depends on ghc-attoparsec
$ guix shell -D guix help2man git strace --pure # & bootstrap & ...
$ ./pre-inst-env guix build ghc-attoparsec-iso8601

After some time, this build failed with:

> phase `setup-compiler' succeeded after 0.1 seconds
> starting phase `configure'
> running "runhaskell Setup.hs" with command "configure" and parameters ("--prefix=/gnu/store/70ddgy9ayd4239dp37b7kvcsdxkg5nrj-ghc-attoparsec-iso8601-1.0.2.0" "--libdir=/gnu/store/70ddgy9ayd4239dp37b7kvcsdxkg5nrj-ghc-attoparsec-iso8601-1.0.2.0/lib" "--docdir=/gnu/store/70ddgy9ayd4239dp37b7kvcsdxkg5nrj-ghc-attoparsec-iso8601-1.0.2.0/share/doc/ghc-attoparsec-iso8601-1.0.2.0" "--libsubdir=$compiler/$pkg-$version" "--package-db=/tmp/guix-build-ghc-attoparsec-iso8601-1.0.2.0.drv-0/package.conf.d" "--global" "--enable-tests" "--enable-shared" "--enable-executable-dynamic" "--ghc-option=-fPIC" "--ghc-option=-optl=-Wl,-rpath=/gnu/store/70ddgy9ayd4239dp37b7kvcsdxkg5nrj-ghc-attoparsec-iso8601-1.0.2.0/lib/$compiler/$pkg-$version")
> Configuring attoparsec-iso8601-1.0.2.0...
> Error:
>     The following packages are broken because other packages they depend on are missing. These broken packages must be rebuilt before they can be used.
> installed package attoparsec-0.14.4 is broken due to missing package scientific-0.3.7.0-9XG3zUjXOw970JFcruv0cZ

Ignorant of the patch provided here, I tried to build newer versions of
ghc-attoparsec / its dependants and ended up with the attached patch.
Using this patch, the build succeeds (but I am not sure if the patch's
approach is sensible).
>From 959dc9de2d4aa39b7490b4c90e28820edf0d00f9 Mon Sep 17 00:00:00 2001
From: itd <[email-masked]>
Date: Fri, 23 Sep 2022 10:58:09 +0200
Subject: [PATCH] WIP update haskell-build-system for newer attoparsec

---
 guix/build/haskell-build-system.scm | 86 +++++++++++++++++------------
 1 file changed, 51 insertions(+), 35 deletions(-)

diff --git a/guix/build/haskell-build-system.scm b/guix/build/haskell-build-system.scm
index ef6cb316ee..d4c4ed4c8c 100644
--- a/guix/build/haskell-build-system.scm
+++ b/guix/build/haskell-build-system.scm
@@ -219,7 +219,10 @@ (define* (register #:key name system inputs outputs #:allow-other-keys)
                    (dep-conf* (string-append dest "/" id ".conf")))
                (when (not (file-exists? dep-conf))
                    (error (format #f "File ~a does not exist. This usually means the dependency ~a is missing. Was checking conf-file ~a." dep-conf id conf-file)))
-               (copy-file dep-conf dep-conf*) ;XXX: maybe symlink instead?
+               ;; Different libraries of same package may share
+               ;; dependencies. Hence, file may exist already.
+               (when (not (file-exists? dep-conf*))
+                   (copy-file dep-conf dep-conf*)) ;XXX: maybe symlink instead?
                (loop (vhash-cons id #t seen)
                      (append lst (conf-depends dep-conf))))
              (loop seen tail))))))
@@ -234,46 +237,59 @@ (define* (register #:key name system inputs outputs #:allow-other-keys)
                                     "/ghc-" version
                                     "/" name ".conf.d"))
          (id-rx (make-regexp "^id:[ \n\t]+([^ \t\n]+)$" regexp/newline))
-         (config-file (string-append out "/" name ".conf"))
+         (maybe-config-file (string-append out "/" name ".conf"))
          (params
-          (list (string-append "--gen-pkg-config=" config-file))))
+          (list (string-append "--gen-pkg-config=" maybe-config-file))))
     (run-setuphs "register" params)
     ;; The conf file is created only when there is a library to register.
-    (when (file-exists? config-file)
+    (when (file-exists? maybe-config-file)
       (mkdir-p config-dir)
-      (let* ((contents (call-with-input-file config-file read-string))
-             (config-file-name+id (match:substring (first (list-matches id-rx contents)) 1)))
+      ;; If more that one library is defined, they share conf file as
+      ;; parent directory.
+      (let* ((config-files (if (file-is-directory? maybe-config-file)
+                             (find-files maybe-config-file)
+                             (list maybe-config-file))))
+        (map
+          (lambda (config-file)
+            (let* ((contents (call-with-input-file config-file read-string))
+                   (config-file-name+id (match:substring (first (list-matches id-rx contents)) 1)))
 
-        (when (or
-                (and
-                  (string? config-file-name+id)
-                  (string-null? config-file-name+id))
-                (not config-file-name+id))
-          (error (format #f "The package id for ~a is empty. This is a bug." config-file)))
+              (when (or
+                      (and
+                        (string? config-file-name+id)
+                        (string-null? config-file-name+id))
+                      (not config-file-name+id))
+                (error (format #f "The package id for ~a is empty. This is a bug." config-file)))
 
-        ;; Remove reference to "doc" output from "lib" (or "out") by rewriting the
-        ;; "haddock-interfaces" field and removing the optional "haddock-html"
-        ;; field in the generated .conf file.
-        (when doc
-          (substitute* config-file
-            (("^haddock-html: .*") "\n")
-            (((format #f "^haddock-interfaces: ~a" doc))
-             (string-append "haddock-interfaces: " lib)))
-          ;; Move the referenced file to the "lib" (or "out") output.
-          (match (find-files doc "\\.haddock$")
-            ((haddock-file . rest)
-             (let* ((subdir (string-drop haddock-file (string-length doc)))
-                    (new    (string-append lib subdir)))
-               (mkdir-p (dirname new))
-               (rename-file haddock-file new)))
-            (_ #f)))
-        (install-transitive-deps config-file %tmp-db-dir config-dir)
-        (rename-file config-file
-                     (string-append config-dir "/"
-                                    config-file-name+id ".conf"))
-        (invoke "ghc-pkg"
-                (string-append "--package-db=" config-dir)
-                "recache")))
+              ;; Remove reference to "doc" output from "lib" (or "out") by rewriting the
+              ;; "haddock-interfaces" field and removing the optional "haddock-html"
+              ;; field in the generated .conf file.
+              (when doc
+                (substitute* config-file
+                  (("^haddock-html: .*") "\n")
+                  (((format #f "^haddock-interfaces: ~a" doc))
+                   (string-append "haddock-interfaces: " lib)))
+                ;; Move the referenced file to the "lib" (or "out") output.
+                (match (find-files doc "\\.haddock$")
+                  ((haddock-file . rest)
+                   (let* ((subdir (string-drop haddock-file (string-length doc)))
+                          (new    (string-append lib subdir)))
+                     (mkdir-p (dirname new))
+                     (rename-file haddock-file new)))
+                  (_ #f)))
+              (install-transitive-deps config-file %tmp-db-dir config-dir)
+              ;; Make current conf file available for possible
+              ;; subsequent conf files.
+              (copy-file config-file
+                         (string-append %tmp-db-dir "/"
+                                        config-file-name+id ".conf"))
+              (rename-file config-file
+                           (string-append config-dir "/"
+                                          config-file-name+id ".conf"))
+              (invoke "ghc-pkg"
+                      (string-append "--package-db=" config-dir)
+                      "recache")))
+          config-files)))
     #t))
 
 (define* (check #:key tests? test-target #:allow-other-keys)

base-commit: a57c4eff6bbdcff79294fa15ecb95ab2b3c55bb4
-- 
2.37.3

Regards
itd