Enabling bitcode for WebRTC iOS

Question

Im having trouble enabling bitcode for webrtc framework ios and running out of ideas. I followed the instructions from their website but im getting error running python build_ios_libs.py --bitcode This is one part of error

../../stats/rtc_stats.cc:30:17: error: loop variable 'element' is always a copy because the range of type 'const std::vector' does not return a reference [-Werror,-Wrange-loop-analysis] for (const T& element : vector)

If anyone made bitcode enable work for webrtc ios, kindly help me thanks

user_1186443 · Answer

You can either wait or fix it yourself!

According to this thread: What is clang's 'range-loop-analysis' diagnostic about?

it is enough to remove the "&" sign from each line that has the problem (the objects are not references anyway in that context and this causes the warning which kills the compilation). So for example:

for (const T& element : vector) {

becomes:

for (const T element : vector) {

Rinse and repeat for all the files the compiler complains about (there are just a few).

user_6577482 · Answer

The answer from a project member in here: https://bugs.chromium.org/p/webrtc/issues/detail?id=11729

"I have talked with Chromium about this and we are not going to land my CL because it is a change to support beta software. The right fix is to file a bug on Apple to ask them to pick up https://reviews.llvm.org/D72212 in xcode 12 (can you do that?) and for now just add treat_warnings_as_errors=false to your args.gn."

user_4933415 · Answer

To save you time. If you're building using, for example:

tools_webrtc/ios/build_ios_libs.py --bitcode --arch arm64 x64

edit these files at line 30 and line 40, respectively and remove the & (ampersand sign) in the for-loops:

stats/rtc_stats.cc:30:8:

sdk/objc/api/peerconnection/RTCStatisticsReport.mm:40:14:

Enabling bitcode for WebRTC iOS

3 Answers