Merge pull request #90 from Anthchirp/cargo_build_target

Use target CARGO_BUILD_TARGET if specified

Author: davidhewitt

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## Unreleased
+
+ - Respect `CARGO_BUILD_TARGET` environment variable if set. [#90](https://github.com/PyO3/setuptools-rust/pull/90)
+
 ## 0.11.5 (2020-11-10)
 
  - Fix support for Python 3.5. [#86](https://github.com/PyO3/setuptools-rust/pull/86)

setuptools_rust/build.py

@@ -92,10 +92,14 @@ def build_extension(self, ext):
 
         # If we are on a 64-bit machine, but running a 32-bit Python, then
         # we'll target a 32-bit Rust build.
+        # Automatic target detection can be overridden via the CARGO_BUILD_TARGET
+        # environment variable.
         # TODO: include --target for all platforms so env vars can't break the build
         target_triple = None
         target_args = []
-        if self.plat_name == "win32":
+        if os.getenv("CARGO_BUILD_TARGET"):
+            target_triple = os.environ["CARGO_BUILD_TARGET"]
+        elif self.plat_name == "win32":
             target_triple = "i686-pc-windows-msvc"
         elif self.plat_name == "win-amd64":
             target_triple = "x86_64-pc-windows-msvc"