DSYM and binary required to symbolicate? Or just D

问题:

Started using Crashlytics and am curious why only the DSYMs have to be uploaded and not the full .app binary to match. I was under the impression that to symbolicate you needed a binary with matching DSYM file. Is that not the case? Basically trying to figure out the magic of how Crashlytics symbolicates when all I do in my app is run the post-build script that uploads the DSYM

回答1:

Mike from Fabric and Crashlytics here.

A dSYM file actually contains all the debug symbols of your app needed to symbolicate the crash report. This is why we recommend having your Debug_Information_Format set to "Dwarf with dSYM". We also generate a unique build id so that even if the build and version number don't change, the dSYM uploaded for that build remains accurate for any crash reports that need to be symbolicated.

You can also read more information on this from Apple, but the most important part is this: "As the compiler translates your source code into machine code, it also generates debug symbols which map each machine instruction in the compiled binary back to the line of source code from which it originated. Depending on the Debug Information Format (DEBUG_INFORMATION_FORMAT) build setting, these debug symbols are stored inside the binary or in a companion Debug Symbol (dSYM) file."

As noted above, the symbols can be in just the dSYM file, hence our recommendation for the setting of Debug_Information_Format.