[lldb-dev] lldb compiled from source 5X slower than homebrew or default lldb

Timothee Cour via lldb-dev lldb-dev at lists.llvm.org
Fri Mar 9 00:59:09 PST 2018

while testing out https://github.com/llvm-mirror/lldb/pull/3 I noticed
that when I compiled lldb from source (even un-modified from git HEAD)
it was 5X slower than homebrew lldb or default lldb:

I'm compiling lldb as follows:
git clone https://github.com/llvm-mirror/llvm.git
cd llvm/tools
git clone https://github.com/llvm-mirror/lldb
## also, patch in https://github.com/llvm-mirror/lldb/pull/3
git clone https://github.com/llvm-mirror/clang
cd ..
mkdir build
cd build
ccmake .. -G Ninja
# here I set: CMAKE_BUILD_TYPE      Release
ninja all

I also tried setting `LLVM_ENABLE_ASSERTIONS OFF` but no difference


./test is some program i have.

time lldb -s commands.txt -- ./test
8 seconds
time ./build/bin/lldb -s commands.txt -- ./test
40 seconds

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