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From: "Csaba Ráduly" <rcsaba@gmail.com>
To: cygwin@cygwin.com
Subject: Re: help compilation qemu
Date: Sun, 24 May 2020 11:25:30 +0200	[thread overview]
Message-ID: <60aeb992-c8ed-d0a0-4473-55c45deb641a@gmail.com> (raw)
In-Reply-To: <CAJzZnfReSV-1dJ6h8pBrxcWFd-5+wA766j_tn3=tOVG-ZEve=A@mail.gmail.com>


Hi Juan Carlos,

On 24/05/2020 02:08, Juan carlos Rebate via Cygwin wrote:
...

> 1 the compiler is extremely slow, gcc on Linux is about 10 times
> faster, How could I speed up the compilation process?.

Unfortunately, Cygwin's emulation of fork() is slow compared to the native Linux 
implementation (I've seen 1000x difference once, in a test launching the same 
program repeatedly). There's not much you can do about it, except getting faster 
hardware. A C++ build involves lots and lots of programs being forked.

> 2 the executables produced are too fat, for example qemu-system-i386 is 65
> MB, but it should be 10.5 MB, if I use the -s option in configure returns
> an unknown error message, how could I fix it? Thank you

Why do you think qemu-system-i386 "should be 10.5 MB" ?
Are you using 32-bit or 64-bit Cygwin? 64-bit executables are usually bigger 
than their 32-bit counterparts (although rarely six times as big).

You really need to give us more information if you hope to get help, like the 
actual commands you used and the exact error message.

Without those, we can only guess, and my crystal ball is not very reliable.

If you want to strip the resulting executables, you could try setting the 
LDFLAGS environment variable to '-s' before running configure

Csaba
-- 
You can get very substantial performance improvements
by not doing the right thing. - Scott Meyers, An Effective C++11/14 Sampler
So if you're looking for a completely portable, 100% standards-conformat way
to get the wrong information: this is what you want. - Scott Meyers (C++TDaWYK)

  reply	other threads:[~2020-05-24  9:25 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-24  0:08 Juan carlos Rebate
2020-05-24  9:25 ` Csaba Ráduly [this message]
2020-05-24 15:30   ` Juan carlos Rebate
2020-05-24 15:41     ` Eliot Moss
2020-05-24 17:45     ` Hans-Bernhard Bröker
  -- strict thread matches above, loose matches on Subject: below --
2020-05-02 19:28 Juan carlos Rebate
2020-05-02 19:33 ` john doe
2020-05-02 20:07   ` Juan carlos Rebate
2020-05-02 20:24 ` Maarten Hoes
2020-05-02 20:41   ` Juan carlos Rebate
     [not found]     ` <CA+GYywAezLvoh+4PhgepphqcEsyUbm_ZOC8yDZqOncVePMzneg@mail.gmail.com>
2020-05-02 22:50       ` Juan carlos Rebate
2020-05-03 12:52     ` Maarten Hoes
2020-05-03 14:54       ` Eliot Moss
2020-05-03 17:09         ` Maarten Hoes

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