From 23cbbe6860782c5d4a0ba599ea1cda0642e91661 Mon Sep 17 00:00:00 2001 From: Christoph Buck Date: Sun, 10 Nov 2024 19:23:01 +0100 Subject: [PATCH] records: Fix ABI check in cross-compilation context. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fixes . * guix/records.scm (define-record-type*)[compute-abi-cookie]: Use 32bit hash value for abi check to prevent `record-abi-mismatch-error` in a cross-compile context. Change-Id: I889747b1a2837bee8bf9b4de5729fdcf1b165380 Signed-off-by: Ludovic Courtès --- guix/records.scm | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/guix/records.scm b/guix/records.scm index dca1e3c2e7..fa2d42e17b 100644 --- a/guix/records.scm +++ b/guix/records.scm @@ -415,11 +415,19 @@ (define (compute-abi-cookie field-specs) ;; list of symbols. (syntax-case field-specs () (((field get properties ...) ...) - (string-hash (object->string - (syntax->datum #'((field properties ...) ...))) - (cond-expand - (guile-3 (target-most-positive-fixnum)) - (else most-positive-fixnum)))))) + ;; Passing (target-most-positive-fixnum) as the second argument of + ;; 'string-hash' won't have the intended effect when cross-compiling + ;; because that second argument is used to compute a modulo after the + ;; hash has been computed on an 'unsigned long'. Instead, only keep + ;; the 32 most significant bits on 64-bit platforms, unconditionally. + ;; See . + (let ((hash-value + (string-hash + (object->string (syntax->datum #'((field properties ...) ...)))))) + (cond + ((< most-positive-fixnum (ash 1 32)) hash-value) + ((< most-positive-fixnum (ash 1 64)) (ash hash-value -32)) + (else (error "unexpected!" most-positive-fixnum))))))) (syntax-case s () ((_ type syntactic-ctor ctor pred