Auto merge of #46273 - semarie:openbsd-libc++, r=alexcrichton

make OpenBSD to use libc++ instead of (e)stdc++

Author: bors

src/librustc_back/target/openbsd_base.rs

@@ -34,6 +34,7 @@ pub fn opts() -> TargetOptions {
         is_like_openbsd: true,
         pre_link_args: args,
         position_independent_executables: true,
+        eliminate_frame_pointer: false, // FIXME 43575
         relro_level: RelroLevel::Full,
         .. Default::default()
     }

src/librustc_llvm/build.rs

@@ -252,8 +252,8 @@ fn main() {
     let llvm_static_stdcpp = env::var_os("LLVM_STATIC_STDCPP");
 
     let stdcppname = if target.contains("openbsd") {
-        // OpenBSD has a particular C++ runtime library name
-        "estdc++"
+        // llvm-config on OpenBSD doesn't mention stdlib=libc++
+        "c++"
     } else if target.contains("netbsd") && llvm_static_stdcpp.is_some() {
         // NetBSD uses a separate library when relocation is required
         "stdc++_pic"

src/libunwind/build.rs

@@ -27,7 +27,7 @@ fn main() {
     } else if target.contains("netbsd") {
         println!("cargo:rustc-link-lib=gcc_s");
     } else if target.contains("openbsd") {
-        println!("cargo:rustc-link-lib=gcc");
+        println!("cargo:rustc-link-lib=c++abi");
     } else if target.contains("solaris") {
         println!("cargo:rustc-link-lib=gcc_s");
     } else if target.contains("bitrig") {

src/test/run-make/tools.mk

@@ -92,7 +92,7 @@ ifeq ($(UNAME),SunOS)
 	EXTRACFLAGS := -lm -lpthread -lposix4 -lsocket -lresolv
 else
 ifeq ($(UNAME),OpenBSD)
-	EXTRACFLAGS := -lm -lpthread
+	EXTRACFLAGS := -lm -lpthread -lc++abi
 	RUSTC := $(RUSTC) -C linker="$(word 1,$(CC:ccache=))"
 else
 	EXTRACFLAGS := -lm -lrt -ldl -lpthread