[Lldb-commits] [lldb] [lldb/DWARF] Remove "range lower than function low_pc" check (PR #132395)

[Pavel Labath via lldb-commits]

labath wrote:

The priority of this has increased from "it's a niche feature only used by google" to "it's used by *everyone*" because (as I was made aware of at the dev meeting), gcc has started producing functions like this on a regular basis. In particular the dynamic loader in the next debian release (trixie)  has functions like this which means that lldb spews a bunch warning when debugging pretty much any binary (if the user has the corresponding debug info package installed):
```
$ lldb usr/lib64/ld-linux-x86-64.so.2 -O "settings set target.debug-file-search-paths ./usr/lib/debug/"
(lldb) settings set target.debug-file-search-paths ./usr/lib/debug/
(lldb) target create "usr/lib64/ld-linux-x86-64.so.2"
Current executable set to '/tmp/debian/usr/lib64/ld-linux-x86-64.so.2' (x86_64).
(lldb) process launch -s
Process 21646 stopped
* thread #1, name = 'ld-linux-x86-64', stop reason = signal SIGSTOP
    frame #0: 0x00007ffff7fe3440 ld-linux-x86-64.so.2`_start
ld-linux-x86-64.so.2`_start:
->  0x7ffff7fe3440 <+0>: movq   %rsp, %rdi
    0x7ffff7fe3443 <+3>: callq  0x7ffff7fe3fb0 ; _dl_start at rtld.c:519:1

ld-linux-x86-64.so.2`_dl_start_user:
    0x7ffff7fe3448 <+0>: movq   %rax, %r12
    0x7ffff7fe344b <+3>: movq   %rsp, %r13
error: ld-linux-x86-64.so.2 0x00085f3b: adding range [0x0000000000001ae8-0x0000000000001b07) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
error: ld-linux-x86-64.so.2 0x00085fdb: adding range [0x0000000000001ae8-0x0000000000001b07) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
error: ld-linux-x86-64.so.2 0x0008601f: adding range [0x0000000000001ae8-0x0000000000001b07) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
error: ld-linux-x86-64.so.2 0x0008603c: adding range [0x0000000000001ae8-0x0000000000001b07) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
error: ld-linux-x86-64.so.2 0x000860ad: adding range [0x0000000000001ae8-0x0000000000001b07) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
error: ld-linux-x86-64.so.2 0x00086120: adding range [0x0000000000001ae8-0x0000000000001b07) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
error: ld-linux-x86-64.so.2 0x00086159: adding range [0x0000000000001ae8-0x0000000000001b07) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
error: ld-linux-x86-64.so.2 0x000863ae: adding range [0x0000000000001a0f-0x0000000000001ae8) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
error: ld-linux-x86-64.so.2 0x000863ef: adding range [0x0000000000001a0f-0x0000000000001ae8) which has a 
base that is less than the function's low PC 0x000000000001cfb0. Please file a bug and attach the file at
 the start of this error message
Process 21646 launched: '/tmp/debian/usr/lib64/ld-linux-x86-64.so.2' (x86_64)
```

https://github.com/llvm/llvm-project/pull/132395