Unable to build with llvm 11.1 on macOS Big Sur #21396

Another macOS build problem, shocking right?

Update 1: I was on the v0.21 branch, will retry on master and maybe open a new issue. Update 2: it also happens on master, reinstalling llvm improved things, but see below

I can build fine with the built in compiler, but I'm trying to build with llvm from homebrew in order to get fuzzing to work.

macOS 11.2.1 Big Sur llvm: stable 11.1.0 (via Homebrew) clang(++) version 11.0.0 Processor type: x86_64h (Intel x86-64h Haswell)

./autogen.sh
./configure CC=/usr/local/opt/llvm/bin/clang CXX=/usr/local/opt/llvm/bin/clang++
...
configure: error: C++ compiler cannot create executables

The CC and CXX commands exist.

Full log: https://gist.github.com/Sjors/dd7920d3f242a5ae75a3fb8232f33987

Potentially relevant log fragment:

configure:4204: /usr/local/opt/llvm/bin/clang++ -qversion >&5
clang-11: error: unknown argument '-qversion'; did you mean '--version'?
clang-11: error: no input files
configure:4215: $? = 1
configure:4235: checking whether the C++ compiler works
configure:4257: /usr/local/opt/llvm/bin/clang++  -I/usr/local/opt/zlib/include -I/usr/local/opt/bzip2/include  -L/usr/local/opt/openssl@1.1/lib -L/usr/local/opt/readline/lib -L/usr/local/opt/zlib/lib -L/usr/local/opt/bzip2/lib conftest.cpp  >&5
ld: warning: directory not found for option '-L/usr/local/opt/bzip2/lib'
ld: library not found for -lc++
clang-11: error: linker command failed with exit code 1 (use -v to see invocation)
configure:4261: $? = 1
configure:4299: result: no
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME "Bitcoin Core"
| #define PACKAGE_TARNAME "bitcoin"
| #define PACKAGE_VERSION "21.99.0"
| #define PACKAGE_STRING "Bitcoin Core 21.99.0"
| #define PACKAGE_BUGREPORT "https://github.com/bitcoin/bitcoin/issues"
| #define PACKAGE_URL "https://bitcoincore.org/"
| /* end confdefs.h.  */
| 
| int
| main ()
| {
| 
|   ;
|   return 0;
| }

Can replicate on a 2020 Macbook Pro macOS 11.2.2 with a fresh install of LLVM off of brew. Ran through your steps and was able to configure and build without errors.

I do get a couple million of the following warning: clang-11: warning: argument unused during compilation: '-fstack-clash-protection' [-Wunused-command-line-argument]

But, the built bitcoind and bitcoin-qt binaries are unusable. They do not work. But I never ran into a fatal error that prevented me from configuring or building.

I see a similar report in my log:

clang-11: error: linker command failed with exit code 1 (use -v to see invocation)
configure:25433: $? = 1
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME "Bitcoin Core"
| #define PACKAGE_TARNAME "bitcoin"
| #define PACKAGE_VERSION "21.99.0"
| #define PACKAGE_STRING "Bitcoin Core 21.99.0"
| #define PACKAGE_BUGREPORT "https://github.com/bitcoin/bitcoin/issues"
| #define PACKAGE_URL "https://bitcoincore.org/"
| #define HAVE_CXX17 1
| #define STDC_HEADERS 1
| #define HAVE_SYS_TYPES_H 1
| #define HAVE_SYS_STAT_H 1
| #define HAVE_STDLIB_H 1
| #define HAVE_STRING_H 1
| #define HAVE_MEMORY_H 1
| #define HAVE_STRINGS_H 1
| #define HAVE_INTTYPES_H 1
| #define HAVE_STDINT_H 1
| #define HAVE_UNISTD_H 1
| #define HAVE_DLFCN_H 1
| #define LT_OBJDIR ".libs/"
| #define USE_ASM 1
| #define ENABLE_SSE41 1
| #define ENABLE_AVX2 1
| #define ENABLE_SHANI 1
| #define HAVE___INT128 1
| #define HAVE_PTHREAD_PRIO_INHERIT 1
| #define HAVE_PTHREAD 1
| #define HAVE_DECL_STRERROR_R 1
| #define HAVE_STRERROR_R 1
| /* end confdefs.h.  */
| 
| int
| main ()
| {
| 
|   ;
|   return 0;
| }

Where your configure fails, mine succeeds:

configure:4204: /usr/local/opt/llvm/bin/clang++ -qversion >&5
clang-11: error: unknown argument '-qversion'; did you mean '--version'?
clang-11: error: no input files
configure:4215: $? = 1
configure:4235: checking whether the C++ compiler works
configure:4257: /usr/local/opt/llvm/bin/clang++    conftest.cpp  >&5
configure:4261: $? = 0
configure:4309: result: yes

full log: https://gist.github.com/jarolrod/93b8bee8e6ee75417188f95bcc4da2b0

Can replicate on a 2020 Macbook Pro macOS 11.2.2 with a fresh install of LLVM off of brew. Ran through your steps and was able to configure and build without errors.

So you mean you can't replicate my error? :-)

I'll go and update macOS to 11.2.3 just in case. It's very strange we don't get the same error, but there might just be a bunch of junk on my system from previous experiments. Come to think of it, I might have been on the v0.21 branch. So I'll retry on the latest master and note the commit...

So you mean you can't replicate my error? :-)

I can configure and build (with 100+ warnings generated) but the binaries don't actually work.

This isn't a Bitcoin Core issue. Your compiler is broken. Does just compiling a program with /usr/local/opt/llvm/bin/clang++ work?

I got the same error on master @ eea6196c3d8056e51e1780a44ac7f599331247e5 on macOS 11.2.2

I reinstalled llvm (which I hadn't done after upgrading to Big Sur). I'm able to compile and run a hello world c++ program with it.

This time I got a bit further, but configuring univalue fails:

./configure CC=/usr/local/opt/llvm/bin/clang CXX=/usr/local/opt/llvm/bin/clang++ --without-gui --disable-zmq --without-miniupnpc --without-natpmp --without-bdb --disable-bench
...
checking for gcc... /usr/local/opt/llvm/bin/clang
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... configure: error: in `/Users/sjors/dev/bitcoin-fuzz/src/univalue':
configure: error: cannot run C compiled programs.
If you meant to cross compile, use `--host'.

Full log.

It seems to think I'm trying to cross compile. If I install Univalue on my system and use --with-system-univalue then the error just repeats for secp256k1.

I got the same error on master @ [eea6196](https://github.com/bitcoin/bitcoin/commit

./configure CC=/usr/local/opt/llvm/bin/clang CXX=/usr/local/opt/llvm/bin/clang++ --without-gui --disable-zmq --without-miniupnpc --without-natpmp --without-bdb --disable-bench
...
checking for gcc... /usr/local/opt/llvm/bin/clang
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... configure: error: in `/Users/sjors/dev/bitcoin-fuzz/src/univalue':
configure: error: cannot run C compiled programs.
If you meant to cross compile, use `--host'.

Full log.

Is this the right log? It doesn't contain the string "cannot run C compiled programs".

Going to close this. I can't recreate the problem, and I'm still convinced this is/was an issue with your system.

Sounds good. I also don't have a Big Sur system anymore.