Auto merge of #74235 - Manishearth:rollup-bgs3q14, r=Manishearth

Rollup of 19 pull requests

Successful merges:

 - #71322 (Accept tuple.0.0 as tuple indexing (take 2))
 - #72303 (Add core::future::{poll_fn, PollFn})
 - #73862 (Stabilize casts and coercions to `&[T]` in const fn)
 - #73887 (stabilize const mem::forget)
 - #73989 (adjust ub-enum test to be endianess-independent)
 - #74045 (Explain effects of debugging options from config.toml)
 - #74076 (Add `read_exact_at` and `write_all_at` to WASI's `FileExt`)
 - #74099 (Add VecDeque::range* methods)
 - #74100 (Use str::strip* in bootstrap)
 - #74103 (Only add CFGuard on `windows-msvc` targets)
 - #74109 (Only allow `repr(i128/u128)` on enum)
 - #74122 (Start-up clean-up)
 - #74125 (Correctly mark the ending span of a match arm)
 - #74127 (Avoid "whitelist")
 - #74129 (:arrow_up: rust-analyzer)
 - #74135 (Update books)
 - #74145 (Update rust-installer to latest version)
 - #74161 (Fix  disabled dockerfiles)
 - #74162 (take self by value in ToPredicate)

Failed merges:

r? @ghost

Author: bors

Cargo.lock

@@ -1366,8 +1366,8 @@ checksum = "7e81a7c05f79578dbc15793d8b619db9ba32b4577003ef3af1a91c416798c58d"
 name = "installer"
 version = "0.0.0"
 dependencies = [
+ "anyhow",
  "clap",
- "failure",
  "flate2",
  "lazy_static",
  "num_cpus",

config.toml.example

@@ -318,7 +318,9 @@
 #codegen-units-std = 1
 
 # Whether or not debug assertions are enabled for the compiler and standard
-# library.
+# library. Debug assertions control the maximum log level used by rustc. When
+# enabled calls to `trace!` and `debug!` macros are preserved in the compiled
+# binary, otherwise they are omitted.
 #
 # Defaults to rust.debug value
 #debug-assertions = false
@@ -331,7 +333,9 @@
 
 # Debuginfo level for most of Rust code, corresponds to the `-C debuginfo=N` option of `rustc`.
 # `0` - no debug info
-# `1` - line tables only
+# `1` - line tables only - sufficient to generate backtraces that include line
+#       information and inlined functions, set breakpoints at source code
+#       locations, and step through execution in a debugger.
 # `2` - full debug info with variable and type information
 # Can be overridden for specific subsets of Rust code (rustc, std or tools).
 # Debuginfo for tests run with compiletest is not controlled by this option