build of clang with LLVM_TARGETS_TO_BUILD set to X86 breaks when building clang shared library

[Quuxplusone]

Bugzilla Link	PR43009
Status	RESOLVED INVALID
Importance	P normal
Reported by	Jerry Scharf (jscharf@purestorage.com)
Reported on	2019-08-15 11:11:36 -0700
Last modified on	2019-08-19 10:52:29 -0700
Version	8.0
Hardware	PC Linux
CC	llvm-bugs@lists.llvm.org, tstellar@redhat.com
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I was building clang 8.0.1 from source and tried using -
DLLVM_TARGETS_TO_BUILD="X86" as part of the cmake input along with shared
libraries. LLVM builds fine, the clang executable builds fine but the clang .so
fails, saying all the other arch entry points are missing. As soon as I change
X86 to all for both llvm and clang, it works fine. I am bootstrapping with
gcc9/ld first in this case.

cmake command for llvm:
 LD_LIBRARY_PATH="/usr/local/compilers/gcc9/lib64" cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=/usr/local/compilers/gcc9/bin/gcc -DCMAKE_CXX_COMPILER=/usr/local/compilers/gcc9/bin/g++ -DCMAKE_INSTALL_PREFIX=/usr/local/compilers/clang8 -DLLVM_TARGETS_TO_BUILD="all" -DLLVM_BUILD_LLVM_DYLIB=true -DLLVM_LINK_LLVM_DYLIB=true ../../llvm-8.0.1.src

clang:

LD_LIBRARY_PATH="/usr/local/compilers/gcc9/lib64" cmake -G "Unix Makefiles" -
DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=/usr/local/compilers/gcc9/bin/gcc -
DCMAKE_CXX_COMPILER=/usr/local/compilers/gcc9/bin/g++ -
DCMAKE_INSTALL_PREFIX=/usr/local/compilers/clang8 -DLLVM_TARGETS_TO_BUILD="all"
-DLLVM_BUILD_LLVM_DYLIB=true -DLLVM_LINK_LLVM_DYLIB=true -DCMAKE_C_FLAGS="-
L/usr/local/compilers/c
lang8/lib" -DCMAKE_CXX_FLAGS="-L/usr/local/compilers/clang8/lib" ../../cfe-
8.0.1.src

[Quuxplusone]

Were you passing -DLLVM_TARGETS_TO_BUILD="X86" to cmake when building both clang and llvm?

[Quuxplusone]

This was a configuration mistake on my part. I conformed that with the correct configuration, this is working correctly.