<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/59228>59228</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            recipe for target 'CMakeFiles/clang_rt.builtins-riscv64.dir/emutls.c.o' failed, build llvm for riscv failed
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          dshm
      </td>
    </tr>
</table>

<pre>
    llvm code is tag llvmorg-15.0.4, build for RISCV target. 

cmake -G "Unix Makefiles" -DGCC_INSTALL_PREFIX=/data/dushaomin/task20221114/insta
lltest20221128 -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;lld;" -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind;libc;compiler-rt"  -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_ASSERTIONS=On -DDEFAULT_SYSROOT="/data/dushaomin/task20221109/test2/install/riscv64-unknown-elf" -DGCC_INSTALL_PREFIX="/data/dushaomin/task20221109/test2/install" -DLLVM_TARGETS_TO_BUILD="RISCV" -DLLVM_DEFAULT_TARGET_TRIPLE="riscv64-unknown-elf" ../llvm

/data/dushaomin/task20221109/test2/install/ is where I install riscv-gnu-toolchain 

make -j

and I get the following error:
[ 93%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/floatunditf.c.o
[ 94%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/floatunsitf.c.o
[ 94%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/floatuntitf.c.o
[ 95%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/multc3.c.o
[ 95%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/powitf2.c.o
[ 96%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/multf3.c.o
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/enable_execute_stack.c:12:10: fatal error: 'sys/mman.h' file not found
#include <sys/mman.h>
         ^~~~~~~~~~~~
[ 97%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/subtf3.c.o
[ 98%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/trunctfdf2.c.o
1 error generated.
[ 98%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/trunctfhf2.c.o
[ 99%] Building C object CMakeFiles/clang_rt.builtins-riscv64.dir/trunctfsf2.c.o
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:52:8: error: unknown type name 'pthread_mutex_t'
static pthread_mutex_t emutls_mutex = PTHREAD_MUTEX_INITIALIZER;
       ^
CMakeFiles/clang_rt.builtins-riscv64.dir/build.make:1780: recipe for target 'CMakeFiles/clang_rt.builtins-riscv64.dir/enable_execute_stack.c.o' failed
make[5]: *** [CMakeFiles/clang_rt.builtins-riscv64.dir/enable_execute_stack.c.o] Error 1
make[5]: *** Waiting for unfinished jobs....
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:52:39: error: use of undeclared identifier 'PTHREAD_MUTEX_INITIALIZER'
static pthread_mutex_t emutls_mutex = PTHREAD_MUTEX_INITIALIZER;
                                      ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:53:8: error: unknown type name 'pthread_key_t'
static pthread_key_t emutls_pthread_key;
       ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:93:3: warning: call to undeclared function 'pthread_setspecific'; ISO C99 and
 later do not support implicit function declarations [-Wimplicit-function-declaration]  pthread_setspecific(emutls_pthread_key, (void *)value);
  ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:97:34: warning: call to undeclared function 'pthread_getspecific'; ISO C99 an
d later do not support implicit function declarations [-Wimplicit-function-declaration]  return (emutls_address_array *)pthread_getspecific(emutls_pthread_key);
                                 ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:118:7: warning: call to undeclared function 'pthread_key_create'; ISO C99 and
 later do not support implicit function declarations [-Wimplicit-function-declaration]  if (pthread_key_create(&emutls_pthread_key, emutls_key_destructor) != 0)
      ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:124:10: error: unknown type name 'pthread_once_t'
  static pthread_once_t once = PTHREAD_ONCE_INIT;
         ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:124:32: error: use of undeclared identifier 'PTHREAD_ONCE_INIT'
  static pthread_once_t once = PTHREAD_ONCE_INIT;
                               ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:125:3: warning: call to undeclared function 'pthread_once'; ISO C99 and later
 do not support implicit function declarations [-Wimplicit-function-declaration]  pthread_once(&once, emutls_init);
  ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:128:42: warning: call to undeclared function 'pthread_mutex_lock'; ISO C99 an
d later do not support implicit function declarations [-Wimplicit-function-declaration]static __inline void emutls_lock(void) { pthread_mutex_lock(&emutls_mutex); }
                                         ^
/data/dushaomin/task20221114/llvm-project/compiler-rt/lib/builtins/emutls.c:130:44: warning: call to undeclared function 'pthread_mutex_unlock'; ISO C99 
and later do not support implicit function declarations [-Wimplicit-function-declaration]static __inline void emutls_unlock(void) { pthread_mutex_unlock(&emutls_mutex); }
                                           ^
6 warnings and 5 errors generated.
CMakeFiles/clang_rt.builtins-riscv64.dir/build.make:1766: recipe for target 'CMakeFiles/clang_rt.builtins-riscv64.dir/emutls.c.o' failed
make[5]: *** [CMakeFiles/clang_rt.builtins-riscv64.dir/emutls.c.o] Error 1
CMakeFiles/Makefile2:303: recipe for target 'CMakeFiles/clang_rt.builtins-riscv64.dir/all' failed
make[4]: *** [CMakeFiles/clang_rt.builtins-riscv64.dir/all] Error 2
Makefile:135: recipe for target 'all' failed
make[3]: *** [all] Error 2
runtimes/CMakeFiles/builtins.dir/build.make:85: recipe for target 'runtimes/builtins-stamps/builtins-build' failed
make[2]: *** [runtimes/builtins-stamps/builtins-build] Error 2
CMakeFiles/Makefile2:100027: recipe for target 'runtimes/CMakeFiles/builtins.dir/all' failed
make[1]: *** [runtimes/CMakeFiles/builtins.dir/all] Error 2
Makefile:155: recipe for target 'all' failed
make: *** [all] Error 2

these days I have been trying to using llvm as the compiler to generate code that can be run on RISCV, and the test platform is spike[https://github.com/riscv-software-src/riscv-isa-sim.git]. I have meet some trouble in build llvm for RISCV and I also raise issues but it is not solved. In this issue, I wiil state the error in detail I met and ask some questions, which I google much time and find many people asked , but there are not a complete answer. 

the main question is Does LLVM libc, compiler-rt and etc support RISCV？ as seen in issue https://github.com/llvm/llvm-project/issues/59026 , it said 
"With respect to libc, it does not work on RISC-V so the libc failures are expected. With respect to compiler-rt, I am not sure if we can list it under LLVM_ENABLE_RUNTIMES. Adding @petrhosek who can confirm/help."
 at the bottom of the webpage. and shown in comipler-rt offical page https://compiler-rt.llvm.org/ platform support section, it said 
"builtins is known to work on the following platforms:
Machine Architectures: i386, X86-64, SPARC64, ARM, PowerPC, PowerPC 64.
OS: DragonFlyBSD, FreeBSD, NetBSD, OpenBSD, Linux, Darwin."
RISCV is not in the list. 
But as the answer in https://github.com/llvm/llvm-project/issues/59026 said by BertalanD, 
"I think your issue is that the command you ran does not build the compiler-rt library, just the compiler. Check out [the documentation](https://llvm.org/docs/HowToCrossCompileBuiltinsOnArm.html) for how to cross-compile the builtins library."
it seems that compiler-rt support RISCV? I tried as he said "-DLLVM_BUILTIN_TARGETS=riscv64-unknown-elf -DBUILTINS_riscv64-unknown-elf_CMAKE_SYSROOT=<path to sysroot>" but failed, and I also tried write compiler-rt libc and etc in -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind;libc;compiler-rt" when cmake, but the build process failed. As seen in officail page https://llvm.org/docs/CMake.html , the target in DLLVM_ENABLE_RUNTIMES is compilerd using just built compiler , thus just built clang target RISCV. 
The answer by different people is contradictory and I am not sure which is right and which wrong.

Could someone please answer me directly? Does llvm support RISCV target completely? Does llvm libc, compiler-rt and etc. supported RISCV? I know using clang with --gcc-toolchain and --sysroot params can generate code for RISCV target, gcc-toolchain and sysroot points to riscv-gnu toolchain install path. But can I use clang without --gcc-toolchain and --sysroot?  Thus using llvm completely without  riscv-gnu toolchain riscv64-unknown-elf-gcc ? As error asked in issue [https://github.com/llvm/llvm-project/issues/59026], there are friendly people answer me that it was the problem of compiler-rt , but I can't build compiler-rt for RISCV successful. Does llvm libc, compiler-rt and etc. supported RISCV?  I have tried much to build it and google it but not make sence. If it support RISCV, Could someone please give a complete proccess how to make it successful, If it not support RISCV, I may not waste time on it.
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzFWllz4rgW_jXkRWUXmP0hD2yZ4d5sBfQy94UStozVsS2uJIfw7-ccyTYmIWuHdFcajCWf9TuLLK1EsDuP4_uE-CJghCui6ZrgDSHXTqPt1t1WzRuRVcbjgIRCktl0PvoOs-SaaZfU6uNafWA__YTeMeL8RWqe9y3lD-QKfoc8ZgpuEGf812i0nF7PF4PLy-XtbHIx_VlrjmveRUA1xa9MRVQkPIVrTdWdV_e8RqMB7C94qmCKYRLHmiltx7weUL28_H61nFwPhpcToHrzn8loMTd0PT-m6brWHJpvRwsRK4c9aEnhXhwH8GnlqlKYfbteTK8mOYWYr_yHB5xuLuiK2-ss3fI0yO8jB5FsQE_pSI0kgeboavDfyXL4bXo5Xi7-uZ0AvRmLGVXsEcPBfD6ZLaY318jyJoXR8eRi8O1ysZz_M5_d3CysJK-Zqd7Hn2iZwlxxDFeSK_--03Ky9C4V29RhcfiiLz7Ip7TiYjD7a7KYLxc3VndL1ECmMqvQ0M5eLmbT28uJnfqMwK4L7BCVVbx90CYI8m3EJCNTkt8lhq2zTjMDEz-iPD2AtkX2r-otmgZAAIKA6IhBZMSxAFCsCZNSyFqzkLE9JP1mzWvX2mMyxCDCOSMiVr-Yr8kIQ-TChsiFwelSaheDTYNoTm4NN-ASxsNYUJ2lAdeh67uiwqD1qQzUqRnopwzan8MgyWLtN09DewP-1aH3iHjn8wQPq4K_JS1iQDgbKZAd8qhmoQtITfBZsINLltJVzJbsgfmZZksAvn_nQvYaNDz8qMMHCYFnXEIYEnlX7fDZJKGpG8FPgvmcpEID4gGKhbBNnvpxBgWk1hwdPNGc2Cmk-FdrT2rd1_725u1-jnlVtjo0L9LufQ5tLbPU12FQhUbD2hDSQ8ok1SxwT8Y3egLJ_qfSVwf0TwDLJNOxMkBsIxB7CLwSgXkdIHq3AdjRhCEmNzqSjAZLeJI9LIFq10oHkNbcJ4-GieVgfwJAx-R28fdsMhgvr74tJj-hDE4X08Hl9H-TGbYEVbgiWM3vdxnO9EoulgyMq27PRJZkPt8w00HZ3gkVeRfZ4_ELnsGopEAk2NcqwAFCwMbwwP6BNsPPYQjYmhh4N17h-INyjQBErbM05ClXEQvIL7FSLvz7Mkw1-4eggi5MhCBRwMAGEiTiAYOqFHIm0S3P4-NkSHvlXwnEExur-b4AvGO758PPDBYmqdx8NshOq1sfdcP_ZEtlynFlMCA-Nn9aVKEQYtbjIq3qqZhWGwjgkPuobXNIpvMbMur3CS1qIIkhzUsSCFMcVbbZCKkJTzYx97neU7V8KF4rjEjnRzHHKeY4lTkYa-SoGL0jloWFGgzcCx7YIOzf0zhj8F2x-VeZu4vmbn3M3usX7G2FD05pb8l0JlGgwsY0CCRT8C0l3eWmPSrrUaf03x7sX-ScRgODvPsx52Bc-3Cl2Z-IBR6iX47JAm1V53hM5HdxcgDLQZn5GpKb1wdKDczSdfRRxUFf5QWvVTbeb8u3IvVZJeES8ijl2nGCXwfl5-Z6NDHV5ykSv1TXpvehOrwX_zM1_7MRCC36h8sRavk09mzU5UqetA5Z_hhv9qqMMGjw9B-pNg0PE1rL-5g9bfsWC__u66tNjuMl2C7mKSOmeOfmtBKZem6yVXdIjolcSXzmtvUATB-_p8X8Quw3MeW1PtgbWM2z9Ii79i_m_oi7CplecFg55bNcVnFapzCmMtmgbfOsevIO4nfWsp3OJ61lczSccvW6Z_F4vXpAp9ikMOvEevNz9DNvmo8q1vptxZB2qZFniRdKmOhqP6vD82I1j4l1jJPE17eJEfRA6kLYY7jpPS9RhVypLsRYsjm4Y6g9I7l3TPL3kH2s4bPoaNTrda_7FlVesszzPmi8oslrVF8CRfv9oHgLGuynjhh0cgHdKTIlEb1nZMUYtLByhy9_MKUrvDDbjFSZ_ZKiWuBokaDsFqSOqIZakAINAspDS0fy_aORyWv4NG7qkA0kedAkwf0cteHGhJHW4OImFjD4W3MdZSsXeNXyrTBHiVBDmmSOkn55kyvqKJ64MB80dAslEgYGUgJacC1FtooZ4Wm-EWpU2e-G2r0gGitBJOUK91FVxhRMhqqjUUBTh0R8D1mYTME0Edwzk1CtKdlyHpuWlhn97MtjjgVKg1tgQgKiIBcowVak_wN9U7eQwDbifoS7UUKsQcwkg1-IGvNIyOEjoemObJjYwDDQYPiCYGTk02YrDExiZKTGMzHT-KzaMnm4xYvCJbg5VrBH3cYCVMWNPWK2Q4FupRcwIjDtl1XYOnNyURuOav0LxINCsPDU2oO84EKzAfik8bC2hot2v-51jF5gc0XxJUjezXg_gAygHxfqGiFXCAoTA5QeVd8KeVegzfkOVjauwJkmNjJ43JiJPSAVdORjqgctELqVJnkDAo_BwnXLDLBjrgwssNGR5Njus0sGgXlzX2vVN0zLSCh2B14W5nlfpCGXaImIxRsXd21t00DtXuRKaC0SXFnhry1bbeiaucYRKsK1JUcaCd_kHhJhyKH5IjjtkfkrGrlodlfINdzex17hVcVMt3TU-EWqQqzki1tRWvtw87Sgq8oN1CvqR9hoDSR8a-CCfsDcxJu9DrL72es4HXNGYX47mI3s5WB2hV-3AhB8O6pcEiijlvDNHKmMJV2L9CLeDedjnHYhGcsvr5nOr242LM0vL3maPeDFmEqQeG98mwjySOdpjh1VHpEYQqjluc8GFk76XawbO692ZMikptA2GBFLu08xzaR3ZCcymQcXnu-IcpgAnwQxAcOQtdJ9INgUV83SiBIIBEmleZ_yK1P6YNwlo4j54E9QErIwDgXCzxJYzBeNM_S8h9pW4ARzUae_xXYhRlIoNbJ0hzlwbtKBTNxIJzF21Zh2AcYm4HCyk0thsV9gLRd37yCEJWNJboCqZoeZqXkBgaslZ5hsCZC0YPa8_PACnmtYTK-Low615vjImQXijPN58-WR4aU9HlI54dEcbSgkE9BJ7ZQUQuPOqeeZDJ1X5rz-5XXGSriVXD9xk1_mXJ6e4njLNoJ8bQ77VGpIjhqAqs-UymWGPLZP7zbN8KN55ikYTLNjfG4yuqn6tmUBUkd1QnAXkgZ5y2GQajCx7zgsuUwdDGLPXTAwOCjidrEPWAi0gIchlMtUF7XU8Ey1pAHHl4q7wkWVxG-LM0yUfB3ZemhvbaVI1261vI5EBjbE-i4g5W3seaGcO1RzaPUgDcQ7xKgpuqYNOYBvoUNRxR9PfqFCuwUlwFUlFBC0uTWtlbZY9Rxn7fuVwzJIw3Fy7IKHJYVIw2J12Nw9PkCGojwlVJIRPNUKg6I8n0P2M4uzOxg4LsH8ivym5q3iXlJMSS8Ki1qSBeKh0qXuzVcSOSrDkdhGXgSJAvRtH2f7rbLBeblNfUveN-l0VOncQkgGaRDvO7wSMibZQerb5rUHSEIja5qDKgSKQJ6iDWE1UBSB6py971TmY5CHWez-BrSKNttmMtuzipwvt4_m_SzXRjiMKHMQS7HUh4ZmGppe4yB7A_-jQbTmwKnS3GKeMokqrySGrqFWqGY6OMOh-g6p5AItOd3ZvpEqbNux3cZ-WLtn7LzR6fQ7Xrfd6J8F582g3-zTM811zM5P9O6kPKJZrkzMQ_nwWSbj898Bnef1zqLzDmt1VrTdCuu05bU7YS9YdYJ6t9fq9trUD5pnMV2xWJ0DwqFOpGxbLHFwjX7Gz4tTm_W-1260XJ-2_G4r7DVWQKfeaUKzy2BxEZed5pk0R1Nhnb5WMIjtlNoPUqX4OmXMsAP6NINAleeBipIzw_fcyP0vOR_4Jg">