Rollup merge of #87307 - michaelwoerister:pgo-unwind-msvc, r=nagisa

Allow combining -Cprofile-generate and -Cpanic=unwind when targeting MSVC.

The LLVM limitation that previously prevented this has been fixed in LLVM 9 which is older than the oldest LLVM version we currently support.

Fixes https://github.com/rust-lang/rust/issues/61002.

r? ``@nagisa`` (or anyone else from ``@rust-lang/wg-llvm)``

1 files changed, 1 insertions, 20 deletions

diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs
index f3ce78d2d78..86d495c3353 100644
--- a/compiler/rustc_session/src/session.rs
+++ b/compiler/rustc_session/src/session.rs
@@ -1,7 +1,7 @@
 use crate::cgu_reuse_tracker::CguReuseTracker;
 use crate::code_stats::CodeStats;
 pub use crate::code_stats::{DataTypeKind, FieldInfo, SizeKind, VariantInfo};
-use crate::config::{self, CrateType, OutputType, PrintRequest, SwitchWithOptPath};
+use crate::config::{self, CrateType, OutputType, SwitchWithOptPath};
 use crate::filesearch;
 use crate::lint::{self, LintId};
 use crate::parse::ParseSess;
@@ -1440,25 +1440,6 @@ fn validate_commandline_args_with_session_available(sess: &Session) {
         }
     }
 
-    // PGO does not work reliably with panic=unwind on Windows. Let's make it
-    // an error to combine the two for now. It always runs into an assertions
-    // if LLVM is built with assertions, but without assertions it sometimes
-    // does not crash and will probably generate a corrupted binary.
-    // We should only display this error if we're actually going to run PGO.
-    // If we're just supposed to print out some data, don't show the error (#61002).
-    if sess.opts.cg.profile_generate.enabled()
-        && sess.target.is_like_msvc
-        && sess.panic_strategy() == PanicStrategy::Unwind
-        && sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs)
-    {
-        sess.err(
-            "Profile-guided optimization does not yet work in conjunction \
-                  with `-Cpanic=unwind` on Windows when targeting MSVC. \
-                  See issue #61002 <https://github.com/rust-lang/rust/issues/61002> \
-                  for more information.",
-        );
-    }
-
     // Sanitizers can only be used on platforms that we know have working sanitizer codegen.
     let supported_sanitizers = sess.target.options.supported_sanitizers;
     let unsupported_sanitizers = sess.opts.debugging_opts.sanitizer - supported_sanitizers;