--- /dev/null
+;;;; Copyright (C) 2008 Free Software Foundation, Inc.
+;;;;
+;;;; This library is free software; you can redistribute it and/or
+;;;; modify it under the terms of the GNU Lesser General Public
+;;;; License as published by the Free Software Foundation; either
+;;;; version 2.1 of the License, or (at your option) any later version.
+;;;;
+;;;; This library is distributed in the hope that it will be useful,
+;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;;;; Lesser General Public License for more details.
+;;;;
+;;;; You should have received a copy of the GNU Lesser General Public
+;;;; License along with this library; if not, write to the Free Software
+;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+;;;;
+
+;;; Commentary:
+
+;;; This code is run during the Guile build, in order to set the stack
+;;; limit to a value that will allow the `make check' tests to pass,
+;;; taking into account the average stack usage on the build platform.
+;;; For more detail, see the text below that gets written out to the
+;;; stack limit calibration file.
+
+;;; Code:
+
+;; Store off Guile's default stack limit.
+(define default-stack-limit (cadr (memq 'stack (debug-options))))
+
+;; Now disable the stack limit, so that we don't get a stack overflow
+;; while running this code!
+(debug-set! stack 0)
+
+;; Define a variable to hold the measured stack high water mark (HWM).
+(define top-repl-hwm-measured 0)
+
+;; Use an evaluator trap to measure the stack size at every
+;; evaluation step, and increase top-repl-hwm-measured if it is less
+;; than the measured stack size.
+(trap-set! enter-frame-handler
+ (lambda _
+ (let ((stack-size (%get-stack-size)))
+ (if (< top-repl-hwm-measured stack-size)
+ (set! top-repl-hwm-measured stack-size)))))
+(trap-enable 'enter-frame)
+(trap-enable 'traps)
+
+;; Call (turn-on-debugging) and (top-repl) in order to simulate as
+;; closely as possible what happens - and in particular, how much
+;; stack is used - when a standard Guile REPL is started up.
+;;
+;; `make check' stack overflow errors have been reported in the past
+;; for:
+;;
+;; - test-suite/standalone/test-use-srfi, which runs `guile -q
+;; --use-srfi=...' a few times, with standard input for the REPL
+;; coming from a shell script
+;;
+;; - test-suite/tests/elisp.test, which does not involve the REPL, but
+;; has a lot of `use-modules' calls.
+;;
+;; Stack high water mark (HWM) measurements show that the HWM is
+;; higher in the test-use-srfi case - specifically because of the
+;; complexity of (top-repl) - so that is what we simulate for our
+;; calibration model here.
+(turn-on-debugging)
+(with-output-to-port (%make-void-port "w")
+ (lambda ()
+ (with-input-from-string "\n" top-repl)))
+
+;; top-repl-hwm-measured now contains the stack HWM that resulted from
+;; running that code.
+
+;; This is the value of top-repl-hwm-measured that we get on a
+;; `canonical' build platform. (See text below for what that means.)
+(define top-repl-hwm-i686-pc-linux-gnu 9461)
+
+;; Using the above results, output code that tests can run in order to
+;; configure the stack limit correctly for the current build platform.
+(format #t "\
+;; Stack limit calibration file.
+;;
+;; This file is automatically generated by Guile when it builds, in
+;; order to set the stack limit to a value that reflects the stack
+;; usage of the build platform (OS + compiler + compilation options),
+;; specifically so that none of Guile's own tests (which are run by
+;; `make check') fail because of a benign stack overflow condition.
+;;
+;; By a `benign' stack overflow condition, we mean one where the test
+;; code is behaving correctly, but exceeds the configured stack limit
+;; because the limit is set too low. A non-benign stack overflow
+;; condition would be if a piece of test code behaved significantly
+;; differently on some platform to how it does normally, and as a
+;; result consumed a lot more stack. Although they seem pretty
+;; unlikely, we would want to catch non-benign conditions like this,
+;; and that is why we don't just do `(debug-set! stack 0)' when
+;; running `make check'.
+;;
+;; Although the primary purpose of this file is to prevent `make
+;; check' from failing without good reason, Guile developers and users
+;; may also find the following information useful, when determining
+;; what stack limit to configure for their own programs.
+
+ (let (;; The stack high water mark measured when starting up the
+ ;; standard Guile REPL on the current build platform.
+ (top-repl-hwm-measured ~a)
+
+ ;; The value of top-repl-hwm-measured that we get when building
+ ;; Guile on an i686 PC GNU/Linux system, after configuring with
+ ;; `./configure --enable-maintainer-mode --with-threads'.
+ ;; (Hereafter referred to as the `canonical' build platform.)
+ (top-repl-hwm-i686-pc-linux-gnu ~a)
+
+ ;; Guile's default stack limit (i.e. the initial, C-coded value
+ ;; of the 'stack debug option). In the context of this file,
+ ;; the important thing about this number is that we know that
+ ;; it allows all of the `make check' tests to pass on the
+ ;; canonical build platform.
+ (default-stack-limit ~a)
+
+ ;; Calibrated stack limit. This is the default stack limit,
+ ;; scaled by the factor between top-repl-hwm-i686-pc-linux-gnu
+ ;; and top-repl-hwm-measured.
+ (calibrated-stack-limit ~a))
+
+ ;; Configure the calibrated stack limit.
+ (debug-set! stack calibrated-stack-limit))
+"
+ top-repl-hwm-measured
+ top-repl-hwm-i686-pc-linux-gnu
+ default-stack-limit
+ ;; Use quotient here to get an integer result, rather than a
+ ;; rational.
+ (quotient (* default-stack-limit top-repl-hwm-measured)
+ top-repl-hwm-i686-pc-linux-gnu))
projects / lilypond.git / blobdiff