From 8b71cb9187bfd0e046c526adcdc2924482b70526 Mon Sep 17 00:00:00 2001
From: Peter Jaszkowiak <p.jaszkow@gmail.com>
Date: Sat, 12 Aug 2023 12:38:34 -0600
Subject: [PATCH 1/2] Enable calling build.rs directly from std/build.rs

---
 build.rs | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/build.rs b/build.rs
index 812fbb1fe..9bd3abd16 100644
--- a/build.rs
+++ b/build.rs
@@ -1,8 +1,10 @@
 extern crate cc;
 
 use std::env;
+use std::path::Path;
 
-fn main() {
+// Must be public so the build script of `std` can call it.
+pub fn main() {
     match env::var("CARGO_CFG_TARGET_OS").unwrap_or_default().as_str() {
         "android" => build_android(),
         _ => {}
@@ -10,7 +12,13 @@ fn main() {
 }
 
 fn build_android() {
-    let expansion = match cc::Build::new().file("src/android-api.c").try_expand() {
+    // Resolve `src/android-api.c` relative to this file.
+    // Required to support calling this from the `std` build script.
+    let android_api_c = Path::new(file!())
+        .parent()
+        .unwrap()
+        .join("src/android-api.c");
+    let expansion = match cc::Build::new().file(android_api_c).try_expand() {
         Ok(result) => result,
         Err(e) => {
             println!("failed to run C compiler: {}", e);

From b90a10505fd6158a0679b99a4220d130d7df8929 Mon Sep 17 00:00:00 2001
From: Peter Jaszkowiak <p.jaszkow@gmail.com>
Date: Sat, 12 Aug 2023 13:12:11 -0600
Subject: [PATCH 2/2] Call buildscript in `as-if-std` buildscript

To test that it will work in the `std` buildscript
---
 crates/as-if-std/Cargo.toml | 4 ++++
 crates/as-if-std/build.rs   | 8 ++++++++
 2 files changed, 12 insertions(+)

diff --git a/crates/as-if-std/Cargo.toml b/crates/as-if-std/Cargo.toml
index 012e60f8f..59eedc506 100644
--- a/crates/as-if-std/Cargo.toml
+++ b/crates/as-if-std/Cargo.toml
@@ -24,6 +24,10 @@ default-features = false
 optional = true
 features = ['read_core', 'elf', 'macho', 'pe', 'unaligned', 'archive']
 
+[build-dependencies]
+# Dependency of the `backtrace` crate
+cc = "1.0.67"
+
 [features]
 default = ['backtrace']
 backtrace = ['addr2line', 'object']
diff --git a/crates/as-if-std/build.rs b/crates/as-if-std/build.rs
index 7018b1017..7669f555d 100644
--- a/crates/as-if-std/build.rs
+++ b/crates/as-if-std/build.rs
@@ -1,3 +1,11 @@
+// backtrace-rs requires a feature check on Android targets, so
+// we need to run its build.rs as well.
+#[allow(unused_extern_crates)]
+#[path = "../../build.rs"]
+mod backtrace_build_rs;
+
 fn main() {
     println!("cargo:rustc-cfg=backtrace_in_libstd");
+
+    backtrace_build_rs::main();
 }