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Reduce command length in regen-ulps [committed]
- From: Joseph Myers <joseph at codesourcery dot com>
- To: <libc-alpha at sourceware dot org>
- Date: Tue, 2 Jan 2018 18:34:06 +0000
- Subject: Reduce command length in regen-ulps [committed]
- Authentication-results: sourceware.org; auth=none
I found that "make regen-ulps" failed when building with unmodified
GNU make 4.1, and an objdir /some/where/math/ longer than about 37
characters, because the list of tests in the "for run in $^" loop
exceeded the Linux kernel's MAX_ARG_STRLEN limit (131072 bytes) on the
length of a single argument passed to a command.
Some GNU/Linux distributions have a patch to make to work around this
limit (see e.g. Debian bug 688601), but clearly this ought to work
without needing such a patch. This patch arranges for the shell loop
to be over the test names without a $(objdir) prefix, which reduces
the space used to less than half MAX_ARG_STRLEN.
(I think we ought to aim to get rid of bits/mathinline.h completely -
filing GCC bugs for any optimizations GCC can't currently do with
-ffast-math - which would mean we could halve the number of libm tests
run because separate inline function tests would no longer be needed.
However, with a long directory name even half the number of tests
could make this command exceed MAX_ARG_STRLEN without my patch.)
Tested regen-ulps on a system where it failed before this patch.
Committed.
2018-01-02 Joseph Myers <joseph@codesourcery.com>
* math/Makefile (run-regen-ulps): Add $(objpfx) to test name here.
(regen-ulps): Use $(libm-tests) not $^ in shell loop.
diff --git a/math/Makefile b/math/Makefile
index e966c98..4c8703c 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -521,12 +521,12 @@ include $(o-iterator)
run-regen-ulps = $(test-wrapper-env) \
$(run-program-env) \
- $($*-ENV) $(rtld-prefix) $${run}
+ $($*-ENV) $(rtld-prefix) $(objpfx)$${run}
regen-ulps: $(addprefix $(objpfx),$(libm-tests))
rm -f $(objpfx)ULPs; rm -f $(objpfx)NewUlps; \
cp $(ulps-file) $(objpfx)libm-test-ulps; \
- for run in $^; do \
+ for run in $(libm-tests); do \
echo "Regenerating ULPs for $${run}"; \
$(run-regen-ulps) -u -o $(objpfx); \
cat $(objpfx)ULPs >> $(objpfx)libm-test-ulps; \
--
Joseph S. Myers
joseph@codesourcery.com