Use CARGO_CFG_TARGET_ARCH in build.rs scripts

Using cargos target flags in build.rs doesn't work because the build.rs is compiled for the host machine and not the target.
dgbo · Mar 4, 2020 · 45be0ab · 45be0ab
1 parent c9f6fc9
commit 45be0ab
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Showing 4 changed files with 20 additions and 12 deletions.
diff --git a/md5/build.rs b/md5/build.rs
@@ -1,9 +1,11 @@
 extern crate cc;
 
 fn main() {
-    let asm_path = if cfg!(target_arch = "x86") {
+    let target_arch = std::env::var("CARGO_CFG_TARGET_ARCH").unwrap_or_default();
+
+    let asm_path = if target_arch == "x86" {
         "src/x86.S"
-    } else if cfg!(target_arch = "x86_64") {
+    } else if target_arch == "x86_64" {
         "src/x64.S"
     } else {
         panic!("Unsupported target architecture");

diff --git a/sha1/build.rs b/sha1/build.rs
@@ -1,17 +1,19 @@
 extern crate cc;
 
 fn main() {
-    let asm_path = if cfg!(target_arch = "x86") {
+    let target_arch = std::env::var("CARGO_CFG_TARGET_ARCH").unwrap_or_default();
+
+    let asm_path = if target_arch == "x86" {
         "src/x86.S"
-    } else if cfg!(target_arch = "x86_64") {
+    } else if target_arch == "x86_64" {
         "src/x64.S"
-    } else if cfg!(target_arch = "aarch64") {
+    } else if target_arch == "aarch64" {
         "src/aarch64.S"
     } else {
         panic!("Unsupported target architecture");
     };
     let mut build = cc::Build::new();
-    if cfg!(target_arch = "aarch64") {
+    if target_arch == "aarch64" {
         build.flag("-march=armv8-a+crypto");
     }
     build.flag("-c")

diff --git a/sha2/build.rs b/sha2/build.rs
@@ -1,18 +1,20 @@
 extern crate cc;
 
 fn main() {
+    let target_arch = std::env::var("CARGO_CFG_TARGET_ARCH").unwrap_or_default();
+
     let mut build256 = cc::Build::new();
-    let (sha256_path, sha512_path) = if cfg!(target_arch = "x86") {
+    let (sha256_path, sha512_path) = if target_arch == "x86" {
         ("src/sha256_x86.S", "src/sha512_x86.S")
-    } else if cfg!(target_arch = "x86_64") {
+    } else if target_arch == "x86_64" {
         ("src/sha256_x64.S", "src/sha512_x64.S")
-    } else if cfg!(target_arch = "aarch64") {
+    } else if target_arch == "aarch64" {
         build256.flag("-march=armv8-a+crypto");
         ("src/sha256_aarch64.S", "")
     } else {
         panic!("Unsupported target architecture");
     };
-    if !cfg!(target_arch = "aarch64") {
+    if target_arch != "aarch64" {
         cc::Build::new()
                   .flag("-c")
                   .file(sha512_path)

diff --git a/whirlpool/build.rs b/whirlpool/build.rs
@@ -1,9 +1,11 @@
 extern crate cc;
 
 fn main() {
-    let asm_path = if cfg!(target_arch = "x86") {
+    let target_arch = std::env::var("CARGO_CFG_TARGET_ARCH").unwrap_or_default();
+
+    let asm_path = if target_arch == "x86" {
         "src/x86.S"
-    } else if cfg!(target_arch = "x86_64") {
+    } else if target_arch == "x86_64" {
         "src/x64.S"
     } else {
         panic!("Unsupported target architecture");