I've been trying to compile syn64k--for use in Executor, to run System's Twilight (a game I played as a kid). I'm doing this on my macbook pro (lion 10.7.4 with the latest Xcode and command line tools). I mapped CC to gcc -m32 to fix a couple problems I was having, but I got the following:
Making all in native/i386
make[2]: Nothing to be done for `all'.
outgoing=;\
gcc -m32 -maccumulate-outgoing-args -c -x c /dev/null 2> /dev/null && outgoing=-maccumulate-outgoing-args; \
gcc -m32 -S -O2 -fomit-frame-pointer -Wall -static -fno-defer-pop -Wno-unused\ -I./include -I./../include -I. -I../include $outgoing syn68k.c -o ./syn68k.s
syn68k.c: In function ‘s68k_handle_opcode_0x07A3’:
syn68k.c:52968: internal compiler error: in EmitLV_DECL, at llvm-convert.cpp:7475
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://developer.apple.com/bugreporter> for instructions.
make[2]: *** [syn68k.o] Error 1
make[1]: *** [all-recursive] Error 1
make: *** [all-recursive] Error 1
I went to URL, and it doesn't look like a place to really put a bug report about LLVM. I the file 'syn68k.c' is about 50k lines long after the preprocessor is done with it, so I really don't thing I can make a reproducible test case to show the bug.
Turns out this issue is already on the github project (it is the only issue listed, ha). MaddTheSane says that this happens because clang does not support global register variables (as I verified here).
I don't really have much more than a basic understanding of how compilation works after you type make, so is there a way I can skip clang or something like that? What do you suggest?
Unfortunately, you need to use gcc, not llvm-gcc to compile this program. The LLVM backend of llvm-gcc does not support global register variables. Switching to clang won't help because it too will choke on the global register variables, for the same reason.
you definitely can skip building clang if its not necessary for what using llvm for.
llvm uses cmake for configuration and the generation of makefiles. you can modify the .cmake files to create a configuration that disables any modules you don't want to create.
http://developer.apple.com/bugreporter is definitely the right place to report a bug against any compiler distributed by Apple, even if it may not look like it. That said, there's no point to filing a bug report against anything other than clang. (BTW, the size of the testcase doesn't really matter.)
If you don't know enough C to hack the source code, it might be worth a shot to grab a newer version of gcc from macports or something like that.
Related
I use QtCreator 4.15.2, clang 12.0.1.
I have "generic project" with makefile. File src/test/main.cpp contains import test.StringUtil;. QtCreator complains that module is not found. (Project builds ok, but makefile uses gcc; I'm not familiar with clang.) I tried this:
Generated .pcm file in separate directory:
clang++ -std=c++20 -fmodules --precompile -x c++-module src/test/StringUtil.cpp -o target/clang/test.StringUtil.pcm
Edited myproject.cxxflags in project root so it contains:
-std=c++20 -fmodules -fprebuilt-module-path=/home/me/myproject/target/clang -Wall -Wextra -Wpedantic -fno-rtti
If I specify relative path -fprebuilt-module-path=target/clang then nothing changes; QtCreator still says that module not found. But with absolute path looks like ClangCodeModel gets disabled (crashes?): <No Symbols> in QtCreator's symbols combobox, no syntax errors reporting.
I also tried to compile in additiion to generating .pcm file, with no difference:
clang++ -std=c++20 -fmodules -c -x c++-module src/test/StringUtil.cpp -o target/build/clang/test.StringUtil.o
So: how do I make it work?
When I added support for modules in my own build system I found it easiest to specify each imported module with the flag -fmodule-file="path/to/other.pcm".
In the future I guess that the big build systems will do this aswell. since you need to preprocess the files anyway there is no extra cost. (It could be some extra work if you write your makefiles by hand though)
I don't think that qtcreators code model supports modules as of yet. I have tried but it does not work for me.
I have been using clang-3.5 to happily build bitcode versions of musl libc and
use the result to produce nice stand alone executables.
Recent attempts with clang-3.8 have not been so happy. It seems that
the bitcode clang-3.8 generates uses functions defined in
compiler-rt/lib/builtins
Typical examples of functions I find polluting the bitcode are mulxc3, mulsc3, and muldc3. I can solve this by linking against libgcc, or even the llvm alternative if I had any clear idea of what that was. Though I would rather prevent the problem from happening in the first place.
I have seen mention of flags like rtlib=compiler-rt etc, but have found precious little documentation on the subject.
So here are some simple questions.
Is it possible to prevent clang from using the compiler-rt/lib/builtins
in the emitted bitcode? Or if not
Does llvm produce a version of libgcc that I could use. Actually I would
probably build a bitcode version of it, but that is besides the point.
Love to hear some guidance on this.
Added 12/8/2016: So I will illustrate my issues with a particular workflow that
people can reproduce if they wish, or, more likely, just point out where I am being stupid.
So start by checking out:
musllv
and follow the instructions in the README.to compile (here I am using clang-3.8 on ubuntu 14.04)
WLLVM_CONFIGURE_ONLY=1 CC=wllvm ./configure --target=LLVM --build=LLVM
make
cd lib
extract-bc -b libc.a
you will also need the bitcode of a simple executable. I will use nweb.c here.
wllvm nweb.c -o nweb
extract-bc nweb
Now we can do things like:
clang -static -nostdlib nweb.bc libc.a.bc crt1.o libc.a -o nweb
This workflow goes smoothly for clang-3.5 but for clang-3.8 we get:
clang -static -nostdlib nweb.bc libc.a.bc crt1.o libc.a -o nweb
/tmp/libc-f734a3.o: In function `cpowl':
libc.a.bc:(.text+0xbb9a): undefined reference to `__mulxc3'
/tmp/libc-f734a3.o: In function `cpowf':
libc.a.bc:(.text+0x38f7d): undefined reference to `__mulsc3'
/tmp/libc-f734a3.o: In function `csqrt':
libc.a.bc:(.text+0x78fc3): undefined reference to `__muldc3'
/tmp/libc-f734a3.o: In function `cpow':
libc.a.bc:(.text+0xafafc): undefined reference to `__muldc3'
clang-3.8: error: linker command failed with exit code 1 (use -v to seeinvocation)
So as #paul-brannan points out we could try
clang -static -nostdlib --rtlib=compiler-rt nweb.bc libc.a.bc crt1.o libc.a -o nweb
But this is where I am probably being stupid, because I get:
clang-3.8: warning: argument unused during compilation: '--rtlib=compiler-rt'
irregardless of whether I use it as a linking or compiling flag.
OK so I finally managed to make headway on this. I built llvm-3.8.1 together with the compiler-rt project using wllvm and wllvm++.
One of the build products was libclang_rt.builtins-x86_64.a,
and from this archive I was able to extract the bitcode module
libclang_rt.builtins-x86_64.bc
using the command:
extract-bc -b libclang_rt.builtins-x86_64.a
This bitcode module has definitions for those pesky instrinsics like
__mulxc3, __mulsc3, and __muldc3.
Hallelujah!
I have been trying to enable the gold linker on FreeBSD to use the link time optimizations. I made gold from the binutils under /usr/ports. After building binutils using make -k install clean i got ld under /usr/bin and in the directory /usr/local/bin i got ld, ld.gold and ld.bfd.
Now while trying to use link time optimization for the simple example programs here http://llvm.org/docs/GoldPlugin.html (a.c and b.c under the heading 'Examples of Link Time Optimization') i entered the four commands as follows:
clang -flto a.c -c -o a.o
ar q a.a a.o
clang b.c -c -o b.o
clang -flto a.a b.o -o main
I got the following error:
usr/bin/ld: unrecogonized option '-plugin'
usr/bin/ld: use the --help option for usage information
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Is there the problem with the linker that ld.gold is not being called. Should I replace the ld with ld.gold? Does the linker looks in the right directiry for the .so plugins?
The LLVMgold.so and libLTO.so shared objects are in the directory /usr/local/llvm-devel/lib/.
I cannot find the directory where clang is installed. I am not sure where to make the bfd-plugins directory and add the symlinks to LLVMgold.so and libLTO.so.
I am using freebsd 10.1 release. How to enable the gold linker for link time optimizations?
also how can I enable it to be the default linker?
You may want to use ld.gold instead of ld. It is installed at /usr/local/bin/ld.gold. If you are using a Makefile, it would work by setting LD variable to ld.gold, either by modifying your Makefile or specifying it on command line. Example in case you are using lang/clang37:
gmake all CC=clang37 LD=ld.gold
EDIT:
It would be even more neat if you add -fuse-ld=gold to your LDFLAGS:
LDFLAGS=-fuse-ld=gold
I'm not sure ld.bfd allows plugins, but I could be wrong.
Your /usr/bin/ld should be a symlink to whatever linker you want. You can change which linker is used by using binutils-config. Check the man-page here: http://www.linuxhowtos.org/manpages/8/binutils-config.htm. I realise this is a Linux link, but it's directed at binutils itself rather than linux-specifically.
It should be something along the lines binutils-config --gold.
On my Gentoo box it is binutils --linker=gold
EDIT: As pointed out, binutils-config doesn't work on BSD it seems. You can still manually update the symlinks though, the downside is that there might be a few of them.
You can find out which ld is used by your compiler by using gcc -print-prog-name=ld or clang -print-prog-name=ld. The file printed should be a symlink you can re-create to point to ld.gold as oposed to ld.bfd.
I am trying to configure util-linux to cross compile using arm-none-linux-gnueabi from CodeSourcery. My only problem so far is that it can't find my ncurses library which I compiled.
How can I add a directory to the ld search path? I've tried adding to my LIBRARY_PATH and LD_LIBRARY_PATH variables, but neither does anything. I know that I can add the -L flag to gcc and it will add to the linker path, but is there any way to do this globally, so that I can do it once, and not have to worry about it again?
Here is the output of arm-none-linux-gnueabi-gcc -print-search-dirs | grep libraries | sed 's/:/\n/g':
libraries
=/tools/bin/../lib/gcc/arm-none-linux-gnueabi/4.6.1/
/tools/bin/../lib/gcc/
/tools/bin/../lib/gcc/arm-none-linux-gnueabi/4.6.1/../../../../arm-none-linux-gnueabi/lib/arm-none-linux-gnueabi/4.6.1/
/tools/bin/../lib/gcc/arm-none-linux-gnueabi/4.6.1/../../../../arm-none-linux-gnueabi/lib/
/tools/bin/../arm-none-linux-gnueabi/libc/lib/arm-none-linux-gnueabi/4.6.1/
/tools/bin/../arm-none-linux-gnueabi/libc/lib/
/tools/bin/../arm-none-linux-gnueabi/libc/usr/lib/arm-none-linux-gnueabi/4.6.1/
/tools/bin/../arm-none-linux-gnueabi/libc/usr/lib/
I would like to add /arm/usr/lib and /arm/usr/local/lib to my ld search path.
If you need output from any other commands, just ask!
EDIT: I just found out about the CFLAGS environment variable--do all configure scripts/makefiles honor it?
Thank you!
If the ncurses library you compiled are going to be linked to the ARM binary you are cross-compiling you can not use LD_LIBRARY_PATH! LD_LIBRARY_PATH is only used by the current run-time and is in no way used by the compiler or linker when building your application.
The use of CFLAGS depends on creator of Makefile. CFLAGS are not automatically used even if they are defined as an environment variable. Only tools like the autoconf tools can pick them up from the environment and use them automagically. In the Makefiles find something like:
$(CC) $(CFLAGS) ....
if this fragment exists then the Makefile uses the CFLAGS variable. LDFLAGS is the more appropriate environment variable to use for link-time options.
(I have the answer to this already; I'm going to answer my own question so that I can share what I've learned and save someone else this trouble in the future)
When I attempt to build Erlang on Solaris 10 Sparcv9, the build fails partway through:
cd lib && \
ERL_TOP=/var/tmp/pkgbuild-0/erlang/sparcv9/erlang-otp-73b4221 PATH=/var/tmp/pkgbuild-0/erlang/sparcv9/erlang-otp-73b4221/bootstrap/bin:${PATH} \
make opt SECONDARY_BOOTSTRAP=true
make[1]: Entering directory `/var/tmp/pkgbuild-0/erlang/sparcv9/erlang-otp-73b4221/lib'
make[2]: Entering directory `/var/tmp/pkgbuild-0/erlang/sparcv9/erlang-otp-73b4221/lib/hipe'
=== Entering application hipe
make[3]: Entering directory `/var/tmp/pkgbuild-0/erlang/sparcv9/erlang-otp-73b4221/lib/hipe/misc'
erlc -W +debug_info +warn_exported_vars +warn_missing_spec +warn_untyped_record -o../ebin hipe_consttab.erl
make[3]: *** [../ebin/hipe_consttab.beam] Bus Error (core dumped)
make[3]: Leaving directory `/var/tmp/pkgbuild-0/erlang/sparcv9/erlang-otp-73b4221/lib/hipe/misc'
Why is this and what can I do to complete my Erlang build?
The reason that the build fails is due to a broken build environment.
In this specific case the Sun GCC build is being used. This particular version of GCC was compiled to use a mixture of the the GNU assembler and the Sun linker.
The Sparc platform is highly sensitive to alignment of code and it will fault (for example, with a bus error) if unaligned code is executed.
The GNU assembler used by the stock GCC build on Sparc Solaris 10 doesn't work so hard to automatically align functions generated by the compiler, leading to unaligned code.
The solution is to build your own GCC and make sure that you use the system assembler and linker; you can achieve this by using the following options to GCC's configure script:
--with-as=/usr/ccs/bin/as \
--without-gnu-as \
--without-gnu-ld \
--with-ld=/usr/ccs/bin/ld \
The resultant GCC build will generated properly aligned code and allow you to build Erlang successfully.