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-rw-r--r--rust/vendor/syn-0.15.44/build.rs76
1 files changed, 76 insertions, 0 deletions
diff --git a/rust/vendor/syn-0.15.44/build.rs b/rust/vendor/syn-0.15.44/build.rs
new file mode 100644
index 0000000..bbdb97e
--- /dev/null
+++ b/rust/vendor/syn-0.15.44/build.rs
@@ -0,0 +1,76 @@
+use std::env;
+use std::process::Command;
+use std::str::{self, FromStr};
+
+// The rustc-cfg strings below are *not* public API. Please let us know by
+// opening a GitHub issue if your build environment requires some way to enable
+// these cfgs other than by executing our build script.
+fn main() {
+ let compiler = match rustc_version() {
+ Some(compiler) => compiler,
+ None => return,
+ };
+
+ if compiler.minor >= 17 {
+ println!("cargo:rustc-cfg=syn_can_match_trailing_dollar");
+ }
+
+ if compiler.minor >= 19 {
+ println!("cargo:rustc-cfg=syn_can_use_thread_id");
+ }
+
+ if compiler.minor >= 20 {
+ println!("cargo:rustc-cfg=syn_can_use_associated_constants");
+ }
+
+ // Macro modularization allows re-exporting the `quote!` macro in 1.30+.
+ if compiler.minor >= 30 {
+ println!("cargo:rustc-cfg=syn_can_call_macro_by_path");
+ }
+
+ if !compiler.nightly {
+ println!("cargo:rustc-cfg=syn_disable_nightly_tests");
+ }
+}
+
+struct Compiler {
+ minor: u32,
+ nightly: bool,
+}
+
+fn rustc_version() -> Option<Compiler> {
+ let rustc = match env::var_os("RUSTC") {
+ Some(rustc) => rustc,
+ None => return None,
+ };
+
+ let output = match Command::new(rustc).arg("--version").output() {
+ Ok(output) => output,
+ Err(_) => return None,
+ };
+
+ let version = match str::from_utf8(&output.stdout) {
+ Ok(version) => version,
+ Err(_) => return None,
+ };
+
+ let mut pieces = version.split('.');
+ if pieces.next() != Some("rustc 1") {
+ return None;
+ }
+
+ let next = match pieces.next() {
+ Some(next) => next,
+ None => return None,
+ };
+
+ let minor = match u32::from_str(next) {
+ Ok(minor) => minor,
+ Err(_) => return None,
+ };
+
+ Some(Compiler {
+ minor: minor,
+ nightly: version.contains("nightly"),
+ })
+}