[PATCH] D157632: [Profile] Allow online merging with debug info correlation.

[Arthur Eubanks via Phabricator via cfe-commits]

aeubanks added inline comments.


================
Comment at: compiler-rt/lib/profile/InstrProfilingMerge.c:146
+    if (!(__llvm_profile_get_version() & VARIANT_MASK_DBG_CORRELATE)) {
+      PROF_ERR("%s\n", "Missing profile data section.");
+      return 1;
----------------
aeubanks wrote:
> ellis wrote:
> > aeubanks wrote:
> > > aeubanks wrote:
> > > > we're running into this error message even though we don't have debug info correlation turned on, is that expected in some configurations? I'm still trying to understand how we could end up in this code path without debug info correlation
> > > > 
> > > > https://crbug.com/1473935
> > > also it seems like this code path isn't tested?
> > It's very strange that you are hitting this code path because I didn't think it was possible. Were you ever able to reproduce locally?
> no, it's only showed up on some bots (both mac and linux), I'm still trying to understand what's going on
managed to repro having no `DataSize` (`NumData` now).

```
$ cat /tmp/a.cc
int main() {}
$ cat /tmp/funlist
[clang]
default:skip
$ clang++ -O1 -fprofile-instr-generate -fcoverage-mapping -o /tmp/a -fuse-ld=lld /tmp/z.cc -fprofile-list=/tmp/funlist
$ export LLVM_PROFILE_FILE='a%m.profraw'
$ /tmp/a
$ /tmp/a
LLVM Profile Error: Missing profile data section.
LLVM Profile Error: Invalid profile data to merge
LLVM Profile Error: Profile Merging of file a18405209413954990729_0.profraw failed: Success
LLVM Profile Error: Failed to write file "a18405209413954990729_0.profraw": Success
```

basically if nothing is instrumented we'll hit this

will revert


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D157632/new/

https://reviews.llvm.org/D157632