Update makefiles for clang 14 or newer
Nobody has claimed this yet.
Assessment
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Newbie friendliness
- 25/100
- Issue type
- Bug
- Clarity
- Mostly clear
- Activity status
- Stale
- Tech stack
- c
- Domain
- build-system
Research direction
Start with 1_square/Makefile and the other example Makefiles, comparing their clang-12 and LLVMEnzyme references with the documented clang/opt workflow. Reproduce the failure on clang 14 or 15, then verify that single-file and multisource examples build and run successfully through the updated make targets.
Written by the indexing model from the issue text.
Description
I'm trying these examples on clang v14 and v15 (on an Ubuntu box) and they fail with some variant of ld.lld: error: undefined symbol: __enzyme_autodiff
or square.c:(.text+0x3a): undefined reference to '__enzyme_autodiff' depending on what linker I use.
For example, using regular gnu ld and making the following changes to the Makefile
$ git diff --word-diff Makefile
diff --git a/1_square/Makefile b/1_square/Makefile
index c223268..b4f278a 100644
--- a/1_square/Makefile
+++ b/1_square/Makefile
@@ -4,7 +4,8 @@ clean:
rm -f *.o *.ll
%.o: %.c
[-../dockerscript.sh clang-12 /host/$^-]{+clang $^+} -O3 -Xclang -load -Xclang [-/Enzyme/enzyme/build/Enzyme/ClangEnzyme-12.so-]{+../../Enzyme/enzyme/build/Enzyme/LLVMEnzyme-14.so+} -ffast-math -o [-/host/$@-]{+$@+}
I obtain:
clang square.c -O3 -Xclang -load -Xclang ../../Enzyme/enzyme/build/Enzyme/LLVMEnzyme-14.so -ffast-math -o square.o
/usr/bin/ld: /tmp/square-977b64.o: in function `main':
square.c:(.text+0x3a): undefined reference to `__enzyme_autodiff'
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [Makefile:7: square.o] Error 1
Adding -fpass-plugin=../../Enzyme/enzyme/build/Enzyme/LLVMEnzyme-14.so for the new pass-manager does not change anything.
The possibly most consequential change to the Makefile is probably the switch from ClangEnzyme-version.so to LLVMEnzyme-version.so. Is that the root cause to this problem? If so, how does one build the former? There is no mention of ClangEnzyme in the cmake_install.cmake of Enzyme version da97fda9aeef27e827a8803f31c40d1b90d0f4a0 (origin/jmp/dataflow-activity-analysis).
As a workaround, I can manually run each step as described at https://enzyme.mit.edu/getting_started/UsingEnzyme/ and that works:
$ clang square.c -S -emit-llvm -o input.ll -O2 -fno-vectorize -fno-slp-vectorize -fno-unroll-loops
$ opt -enable-new-pm=0 input.ll -load=../../Enzyme/enzyme/build/Enzyme/LLVMEnzyme-14.so -enzyme -o output.ll -S
$ opt output.ll -O2 -o output_opt.ll -S
$ clang output_opt.ll -o a.exe
$ ./a.exe 3.14
Gradient square(3.140000) = 6.280000
However that is good only for single-file examples. The optcommand can't be made to work for multisource, as far as I understand it, since both opt and clang -S can only deal with one source file at the time and one would need two for this purpose:
$ clang multisource.c -S -emit-llvm -o multisource.ll -fno-vectorize -fno-slp-vectorize -fno-unroll-loops
$ clang myblas.c -S -emit-llvm -o myblas.ll -fno-vectorize -fno-slp-vectorize -fno-unroll-loops
$ opt -enable-new-pm=0 myblas.ll -load=../../Enzyme/enzyme/build/Enzyme/LLVMEnzyme-14.so -enzyme -o myblas_out.ll -S
$ opt -enable-new-pm=0 multisource.ll -load=../../Enzyme/enzyme/build/Enzyme/LLVMEnzyme-14.so -enzyme -o multisource_out.ll -S
error: <unknown>:0:0: in function preprocess_dotabs double (%struct.complex*, %struct.complex*, i32): Enzyme: No reverse pass found for myblas_cabs
at context: %7 = call double @myblas_cabs(double %5, double %6) #7
$ opt -enable-new-pm=0 myblas.ll multisource.ll -load=../../Enzyme/enzyme/build/Enzyme/LLVMEnzyme-14.so -enzyme -o multisource+myblas_out.ll -S
opt: Too many positional arguments specified!
Can specify at most 1 positional arguments: See: opt --help
$ clang multisource.c myblas.c -S -emit-llvm -o multisource+myblas.ll -fno-vectorize -fno-slp-vectorize -fno-unroll-loops
clang: error: cannot specify -o when generating multiple output files
so how can one fix that case?
@wsmoses sorry if the question is very trivial, but I've been unable to find guidance in the existing examples and documentation, either here or on https://github.com/EnzymeAD/Enzyme
- Dominant language
- Jupyter Notebook
- Stars
- 21
- Forks
- 8
- PR merge metrics
- No merged PRs in 30d
Getting set up
This project ships no dev container, Dockerfile or contributing guide, so setting up is up to you: start from its README, and see our first-contribution guide for the general steps.
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
More from EnzymeAD/Enzyme-Tutorial
-
Difficulty 4/5 3-5 days Newbie friendliness 25/100
EnzymeAD/Enzyme-Tutorial#11 ·
-
Difficulty 4/5 3-5 days Newbie friendliness 35/100
EnzymeAD/Enzyme-Tutorial#10 ·
-
Difficulty 3/5 1-2 days Newbie friendliness 35/100
-
Difficulty 3/5 1-2 days Newbie friendliness 35/100
EnzymeAD/Enzyme-Tutorial#8 · 2 comments ·
-
Link to talkOpen
Difficulty 1/5 Under an hour Newbie friendliness 35/100
EnzymeAD/Enzyme-Tutorial#4 · 2 reactions ·
All issues in EnzymeAD/Enzyme-Tutorial
Similar issues
-
Difficulty 2/5 1-3 hours Newbie friendliness 65/100
-
Difficulty 2/5 1-3 hours Newbie friendliness 84/100
objectionary/hone-maven-plugin#1295 ·
Maintainers usually reply within 1 day
-
Difficulty 1/5 Under an hour Newbie friendliness 78/100
espressif/esp-matter#1874 ·
-
cudev: Fix MSVC build failures with 64-bit integers (int64_t/uint64_t) in vec_traits.hppPossibly taken A pull request linked to this issue is open or already merged. Open
Difficulty 2/5 1-3 hours Newbie friendliness 78/100
opencv/opencv_contrib#4231 ·
Maintainers usually reply within 1 day
-
Difficulty 2/5 1-3 hours Newbie friendliness 72/100
linux-test-project/lcov#552 ·
Maintainers usually reply within 1 day