Clean up cfgs for crate includes.

The existing dependency cfgs are a mess. Rework them based on a few principles.

1. Windows targets use PDBs if compiled with MSVC, or DWARF if compiled with the GNU toolchain. Gate addr2line and object, which is only used with addr2line, on not(msvc).
2. Windows targets never use ELF. Gate miniz_oxide and zstd, which are used for ELF compression, on not(windows).
3. libc is used by the addr2line code, Fuschia specific code (which implies DWARF), and libunwind specific code (which implies DWARF), so gate it on not(msvc) as well.
4. The Windows UWP target only allows a reduced set of APIs. That set of APIs excludes some used by addr2line, so additionally gate all the DWARF related crates on not(uwp).

Cargo.toml

@@ -39,15 +39,21 @@ cpp_demangle = { default-features = false, version = "0.4.0", optional = true, f
   "alloc",
 ] }
 
-[target.'cfg(not(all(windows, target_env = "msvc", not(target_vendor = "uwp"))))'.dependencies]
-miniz_oxide = { version = "0.7.0", default-features = false }
+# MSVC uses PDB, not DWARF. But UWP doesn't allow for APIs gimli (via addr2line) uses,
+# so skip that too.
+[target.'cfg(not(any(target_env = "msvc", target_vendor = "uwp")))'.dependencies]
 addr2line = { version = "0.22.0", default-features = false }
 libc = { version = "0.2.146", default-features = false }
 
-[target.'cfg(not(any(all(windows, target_env = "msvc", not(target_vendor = "uwp")), target_os = "illumos")))'.dependencies]
+# Windows uses PE, not ELF, so libraries for ELF compression are unnecessary.
+[target.'cfg(not(windows))'.dependencies]
+miniz_oxide = { version = "0.7.0", default-features = false }
+
+# Also used for ELF compression, but doesn't build on illumos in CI.
+[target.'cfg(not(any(windows, target_os = "illumos")))'.dependencies]
 zstd = { version = "= 0.13.0", default-features = false }
 
-[target.'cfg(not(all(windows, target_env = "msvc", not(target_vendor = "uwp"))))'.dependencies.object]
+[target.'cfg(not(any(target_env = "msvc", target_vendor = "uwp")))'.dependencies.object]
 version = "0.35.0"
 default-features = false
 features = ['read_core', 'elf', 'macho', 'pe', 'xcoff', 'unaligned', 'archive']

crates/as-if-std/Cargo.toml

@@ -14,16 +14,18 @@ bench = false
 [dependencies]
 cfg-if = "1.0"
 rustc-demangle = "0.1.21"
+
+[target.'cfg(not(any(target_env = "msvc", target_vendor = "uwp")))'.dependencies]
 libc = { version = "0.2.146", default-features = false }
+addr2line = { version = "0.22.0", optional = true, default-features = false }
 
-[target.'cfg(not(all(windows, target_env = "msvc", not(target_vendor = "uwp"))))'.dependencies]
+[target.'cfg(not(windows))'.dependencies]
 miniz_oxide = { version = "0.7.0", optional = true, default-features = false }
-addr2line = { version = "0.22.0", optional = true, default-features = false }
 
-[target.'cfg(not(any(all(windows, target_env = "msvc", not(target_vendor = "uwp")), target_os = "illumos")))'.dependencies]
+[target.'cfg(not(any(windows, target_os = "illumos")))'.dependencies]
 zstd = { version = "= 0.13.0", optional = true, default-features = false }
 
-[target.'cfg(not(all(windows, target_env = "msvc", not(target_vendor = "uwp"))))'.dependencies.object]
+[target.'cfg(not(any(target_env = "msvc", target_vendor = "uwp")))'.dependencies.object]
 version = "0.35.0"
 default-features = false
 optional = true