Rollup merge of #113593 - rcvalle:rust-cfi-fix-90546, r=wesleywiser

CFI: Fix error compiling core with LLVM CFI enabled

Fix #90546 by filtering out global value function pointer types from the type tests, and adding the LowerTypeTests pass to the rustc LTO optimization pipelines.

3 files changed, 16 insertions, 4 deletions

diff --git a/compiler/rustc_session/messages.ftl b/compiler/rustc_session/messages.ftl
index d4042a2e61a..b07c6db599e 100644
--- a/compiler/rustc_session/messages.ftl
+++ b/compiler/rustc_session/messages.ftl
@@ -89,7 +89,9 @@ session_sanitizer_cfi_generalize_pointers_requires_cfi = `-Zsanitizer-cfi-genera
 
 session_sanitizer_cfi_normalize_integers_requires_cfi = `-Zsanitizer-cfi-normalize-integers` requires `-Zsanitizer=cfi` or `-Zsanitizer=kcfi`
 
-session_sanitizer_cfi_requires_lto = `-Zsanitizer=cfi` requires `-Clto`, `-Clto=thin`, or `-Clinker-plugin-lto`
+session_sanitizer_cfi_requires_lto = `-Zsanitizer=cfi` requires `-Clto` or `-Clinker-plugin-lto`
+
+session_sanitizer_cfi_requires_single_codegen_unit = `-Zsanitizer=cfi` with `-Clto` requires `-Ccodegen-units=1`
 
 session_sanitizer_not_supported = {$us} sanitizer is not supported for this target
 
diff --git a/compiler/rustc_session/src/errors.rs b/compiler/rustc_session/src/errors.rs
index 1ffee01b2f1..78940462b2c 100644
--- a/compiler/rustc_session/src/errors.rs
+++ b/compiler/rustc_session/src/errors.rs
@@ -115,6 +115,10 @@ pub struct CannotEnableCrtStaticLinux;
 pub struct SanitizerCfiRequiresLto;
 
 #[derive(Diagnostic)]
+#[diag(session_sanitizer_cfi_requires_single_codegen_unit)]
+pub struct SanitizerCfiRequiresSingleCodegenUnit;
+
+#[derive(Diagnostic)]
 #[diag(session_sanitizer_cfi_canonical_jump_tables_requires_cfi)]
 pub struct SanitizerCfiCanonicalJumpTablesRequiresCfi;
 
diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs
index ac745d16161..b25a6299125 100644
--- a/compiler/rustc_session/src/session.rs
+++ b/compiler/rustc_session/src/session.rs
@@ -1619,13 +1619,19 @@ fn validate_commandline_args_with_session_available(sess: &Session) {
 
     // LLVM CFI requires LTO.
     if sess.is_sanitizer_cfi_enabled()
-        && !(sess.lto() == config::Lto::Fat
-            || sess.lto() == config::Lto::Thin
-            || sess.opts.cg.linker_plugin_lto.enabled())
+        && !(sess.lto() == config::Lto::Fat || sess.opts.cg.linker_plugin_lto.enabled())
     {
         sess.emit_err(errors::SanitizerCfiRequiresLto);
     }
 
+    // LLVM CFI using rustc LTO requires a single codegen unit.
+    if sess.is_sanitizer_cfi_enabled()
+        && sess.lto() == config::Lto::Fat
+        && !(sess.codegen_units().as_usize() == 1)
+    {
+        sess.emit_err(errors::SanitizerCfiRequiresSingleCodegenUnit);
+    }
+
     // LLVM CFI is incompatible with LLVM KCFI.
     if sess.is_sanitizer_cfi_enabled() && sess.is_sanitizer_kcfi_enabled() {
         sess.emit_err(errors::CannotMixAndMatchSanitizers {