System details first: "CYGWIN_NT-5.1 GKDC531 2.5.2(0.297/5/3) 2016-06-23
14:27 i686" on Windows XP SP3, on a dual-core Pentium 4 (i786) box.
I have rebuilt and optimized gcc and several math libraries with the
architecture-specific options of gcc, `-march=native' and
`-mfpmath=sse', to get the most out of my old box. This strategy has
proven successful; my gcc build runs noticeably faster than the
distribution version. Ultimately, I hope to build an ffmpeg that also
runs a bit faster. (As things are, ffmpeg can take *days* to recode a
feature-length video on my box.)
Following the instructions in section 6.21 of the FAQ, I installed the
various build tools (cocom, etc.) and then...
$ (/home/projects/newlib-cygwin/configure --prefix=/usr -v CFLAGS='-O3
-march=native -mfpmath=sse' CXXFLAGS='-O3 -march=native -mfpmath=sse';
make) |& tee build.log
configure: loading site script /usr/share/config.site
checking build system type... i686-pc-cygwin
checking host system type... i686-pc-cygwin
checking target system type... i686-pc-cygwin
checking for a BSD-compatible install... /bin/install -c
checking whether ln works... yes
.
.
checking for isl 0.16, 0.15, or deprecated 0.14... yes \ ?
checking for isl 0.16 or 0.15... no / ?
.
[Everything going well, until...]
.
checking for i686-w64-mingw32-gcc... i686-w64-mingw32-gcc
checking for x86_64-w64-mingw32-gcc... no
configure: error: no acceptable mingw64 cc found in $PATH
^^^^^^^^^^---------------------------???????
configure: error: /home/projects/newlib-cygwin/winsup/lsaauth/configure
failed for lsaauth
make[1]: *** [Makefile:9420: configure-target-winsup] Error 1
make[1]: Leaving directory '/home/projects/cygwin_build'
make: *** [Makefile:883: all] Error 2
I am sure I have all the support libraries for the 32-bit mingw gcc
installed and working (I've built software with it). Does this mean a
64-bit machine is required to build the Cygwin DLL?
I tried the Newlib-Cygwin distribution sources, and I downloaded the
sources from git://sourceware.org, all with the same result.
A Google search turned up only one article that might be helpful:
"After a great struggle (and lots of googling around) i finally compiled
cygwin1.dll on linux and tested in a win32 environment, the process
wasn't straightforward but it worked."
https://cygwin.com/ml/cygwin-developers/2010-08/txt00000.txt
Some of this I could follow, but some of it was well beyond me.
Really, all I need from the Newlib-Cygwin package are libm and the
Cygwin dll, optimized by being built architecturally specific so that I
can build ffmpeg (and maybe some other things, similarly optimized) on
this platform, and hope they do not take days to complete a job.
Please help?
Jeff
By the way, how is cocom to be used to build Newlib and the DLL? What
little documentation that comes with the Cygwin package is.... intriguing...
--
Problem reports: http://cygwin.com/problems.html
FAQ: http://cygwin.com/faq/
Documentation: http://cygwin.com/docs.html
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
