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mirror of https://git.FreeBSD.org/ports.git synced 2025-01-09 06:51:44 +00:00

Fix a mistake in the directions for creating symlinks. Add instructions for

creating a gcc specs file (prompted by Dima Ruben).  Remove obsolete
information and update various tidbits.
This commit is contained in:
Jason Evans 2000-07-12 02:08:45 +00:00
parent 20a05fe918
commit 8ec27f4ca8
Notes: svn2git 2021-03-31 03:12:20 +00:00
svn path=/head/; revision=30502

View File

@ -1,9 +1,13 @@
Some brief notes:
1) This package is intended to run on FreeBSD 5.0-current or
FreeBSD 4.X i386 processors only.
1) This package is intended to run on FreeBSD 5.0-current or FreeBSD 4.X, i386
processors only.
Compile your applications that use LinuxThreads with the following
Do not use libc_r with the linuxthreads port, and do not compile/link with the
-pthread option (which pulls in libc_r). Rather, link with libc (which you will
get by default).
Compile your applications that use the linuxthreads port with the following
command line options:
-D_THREAD_SAFE -I/usr/local/include/pthread/linuxthreads -llthread -llgcc_r
@ -11,7 +15,7 @@ command line options:
Note that the include (-I<path>) directive shown here should appear before any
other include directive that would cause the compiler to find the FreeBSD file
/usr/include/pthread.h. Using the FreeBSD pthread.h instead of the linuxthreads
pthread.h will result in an app fails fails in many odd and maybe spectacular
pthread.h will result in an app that fails in many odd and maybe spectacular
ways.
In order to facilitate porting applications which expect a libpthread, you can
@ -20,35 +24,35 @@ create the following symlinks if you want:
ln -s /usr/local/lib/liblthread.a /usr/lib/libpthread.a
ln -s /usr/local/lib/liblthread_p.a /usr/lib/libpthread_p.a
ln -s /usr/local/lib/liblthread.so.2 /usr/lib/libpthread.so.2
ln -s /usr/local/lib/liblthread.so.0 /usr/lib/libpthread.so
ln -s /usr/local/lib/liblthread.so.2 /usr/lib/libpthread.so
/sbin/ldconfig -m /usr/lib
If you do this, you can instead use:
-D_THREAD_SAFE -I/usr/local/include/pthread/linuxthreads -lpthread -llgcc_r
or
-D_THREAD_SAFE -I/usr/local/include/pthread/linuxthreads -kthread -llgcc_r
Do not use libc_r with LinuxThreads, and do not compile/link with the -pthread
option (which pulls in libc_r). Rather, link with libc (which you will get by
default).
Another option is to create a custom gcc specs file that tells the linker which
version of libgcc to use. To do this, create a file with the following in it:
2) You should consider enabling the posix priority extensions in your kernel.
Adding the following to your kernel config file before you execute config and
before you re-make the kernel should suffice.
--- (/foo/specs) cut here ---
*libgcc:
/usr/local/lib/liblgcc_r.a
--- (/foo/specs) cut here ---
options "P1003_1B"
options "_KPOSIX_PRIORITY_SCHEDULING"
options "_KPOSIX_VERSION=199309L"
Then use the following command line options:
These options are not mandatory.
-B/foo/ -D_THREAD_SAFE -I/usr/local/include/pthread/linuxthreads -llthread
3) If you plan on having lots of threads, check the sysctl value of
or if you created symlinks:
-B/foo/ -D_THREAD_SAFE -I/usr/local/include/pthread/linuxthreads -lpthread
2) If you plan on having lots of threads, check the sysctl value of
kern.maxproc. Each kernel thread counts against maxproc. You can increase
maxproc by changing the MAXUSERS value in your kernel config file. maxproc is
set at 20 + 16 * MAXUSERS.
4) Be aware of the following libc issues:
3) Be aware of the following libc issues:
a) Not all libc calls are thread safe. In particular gmtime, localtime, etc
are not thread safe. In general, where the pthreads spec calls for "_r"
@ -61,19 +65,3 @@ set at 20 + 16 * MAXUSERS.
implemented as such. While linux threads has the cancel functions
implemented, deferred cancellation will not work as required by POSIX
1003.1c-1995, since the co-operation needed from libc is not complete.
5) Known problems and issues:
It is possible that the instructions given above for including liblgcc_r
are not sufficent. liblgcc_r is a version of libgcc_r linked against this
linuxthreads package. It is intended that applications link against this,
rather than libgcc_r (which is linked against libc_r) or libgcc (which is not
thread safe).
The normal gcc link options cause libgcc to be included twice in the link line
(and libgcc_r twice when linking with the -pthread option). It is therefore
possible that a custom link line needs to be generated that specifically
excludes the default libgcc and which includes liblgcc_r twice. There are no
known problems resulting from the link procedure suggested above. However,
compiling/linking with the "-v" option will illustrate the issue, where libgcc
is included twice in addition to liblgcc_r.