bear generate redundant database when using wllvm

[hongxuchen]

This is a rare use-case: when using wllvm Bear always generates more compilation database entries than expected.

As the README.md mentioned, that project does 2 things when CC=wllvm and CXX=wllvm++ during compilation:

• invoke regular compiler to build a real object
• Do bitcode compilation with the corresponding compiler commands specified.

In this sense, I was hoping

min.out: main.o min.o
        $(CC) main.o min.o -o $@
main.o:
        $(CC) main.c -c -o $@ 
min.o:
        $(CC) min.c -c -o $@

Will generate compile commands like:

clang main.c -c -o main.o
clang min.c -c -o min.o
clang -emit-llvm main.c -c -o .main.o.bc
clang -emit-llvm main.c -c -o .min.o.bc

But the inside compiler_commands.json there are 9 entries for the same compilation commands for each build target. Also I notice that wllvm seems correct here since when set WLLVM_OUTPUT=debug it only prints each compilation once. So this may be an issue for Bear.
But as my case is not the regular compilation practice, I guess this should be of low priority.

[rizsotto]

thanks for the report. compiler wrappers are root of problems as i mentioned in the documentation.
the next release will contain fix for detecting (and filtering) potential duplicates.

[hongxuchen]

@rizsotto Sorry I didn't read the document carefully. Just treat this as a reminder:-)

[rizsotto]

there is a new version of the tool, which filters the compiler wrappers now. please give it a try and reopen this issue if that's still a case.

[hongxuchen]

Works like a charm, many thanks!