From dd554dff11e0d36b3012e531d3ebb1c9edd5eee4 Mon Sep 17 00:00:00 2001
From: Philipp Oppermann <dev@phil-opp.com>
Date: Thu, 20 Aug 2020 13:51:53 +0200
Subject: [PATCH] Allow to unset a default target by setting `build.target` to
 the empty string

---
 src/cargo/core/compiler/compile_kind.rs |  6 ++++-
 tests/testsuite/cross_compile.rs        | 31 +++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/src/cargo/core/compiler/compile_kind.rs b/src/cargo/core/compiler/compile_kind.rs
index 4c123601f8e..f099db8ec8f 100644
--- a/src/cargo/core/compiler/compile_kind.rs
+++ b/src/cargo/core/compiler/compile_kind.rs
@@ -72,7 +72,11 @@ impl CompileKind {
                 } else {
                     val.raw_value().to_string()
                 };
-                CompileKind::Target(CompileTarget::new(&value)?)
+                if value == "" {
+                    CompileKind::Host
+                } else {
+                    CompileKind::Target(CompileTarget::new(&value)?)
+                }
             }
             None => CompileKind::Host,
         };
diff --git a/tests/testsuite/cross_compile.rs b/tests/testsuite/cross_compile.rs
index fe573a88270..a854cec91fa 100644
--- a/tests/testsuite/cross_compile.rs
+++ b/tests/testsuite/cross_compile.rs
@@ -117,6 +117,37 @@ fn simple_cross_config() {
     }
 }
 
+#[cargo_test]
+fn unset_default_target() {
+    let p = project()
+        .file(
+            ".cargo/config",
+            r#"
+            [build]
+            target = ""
+            "#,
+        )
+        .file(
+            "Cargo.toml",
+            r#"
+            [package]
+            name = "foo"
+            version = "0.0.0"
+            authors = []
+        "#,
+        )
+        .file(
+            "src/main.rs",
+            r#"
+                fn main() {{}}
+            "#,
+        )
+        .build();
+
+    p.cargo("build -v").run();
+    assert!(p.bin("foo").is_file());
+}
+
 #[cargo_test]
 fn simple_deps() {
     if cross_compile::disabled() {