Rollup merge of #71929 - petrhosek:unwind-visibility, r=tmandry

Dylan-DPC · web-flow · commit c366b27bfcf0 · 2020-05-06T16:59:00.000+02:00
Use -fvisibility=hidden for libunwind

We don't want to export any symbols from Rust's version of libunwind
as these may collide with other copies of libunwind e.g. when linking
Rust staticlib together C/C++ libraries that have their own version.
diff --git a/src/libunwind/build.rs b/src/libunwind/build.rs
@@ -89,6 +89,7 @@ mod llvm_libunwind {
             cfg.flag("-fno-rtti");
             cfg.flag("-fstrict-aliasing");
             cfg.flag("-funwind-tables");
+            cfg.flag("-fvisibility=hidden");
         }
 
         let mut unwind_sources = vec![

Original file line number	Diff line number	Diff line change
`@@ -89,6 +89,7 @@ mod llvm_libunwind {`
`89`	`89`	`cfg.flag("-fno-rtti");`
`90`	`90`	`cfg.flag("-fstrict-aliasing");`
`91`	`91`	`cfg.flag("-funwind-tables");`
	`92`	`+ cfg.flag("-fvisibility=hidden");`
`92`	`93`	`}`
`93`	`94`
`94`	`95`	`let mut unwind_sources = vec![`