Merge "Revert^4 "Enable full LTO optimization by default"" into main

1 files changed, 5 insertions, 6 deletions

diff --git a/cc/lto.go b/cc/lto.go
index 60eb4d6b1..44441527a 100644
--- a/cc/lto.go
+++ b/cc/lto.go
@@ -54,6 +54,9 @@ type LTOProperties struct {
 
 	// Use -fwhole-program-vtables cflag.
 	Whole_program_vtables *bool
+
+	// Use --lto-O0 flag.
+	Lto_O0 *bool
 }
 
 type lto struct {
@@ -106,12 +109,8 @@ func (lto *lto) flags(ctx ModuleContext, flags Flags) Flags {
 		ltoCFlags := []string{"-flto=thin", "-fsplit-lto-unit"}
 		var ltoLdFlags []string
 
-		// The module did not explicitly turn on LTO. Only leverage LTO's
-		// better dead code elimination and CFG simplification, but do
-		// not perform costly optimizations for a balance between compile
-		// time, binary size and performance.
-		// Apply the same for Eng builds as well.
-		if !lto.ThinLTO() || ctx.Config().Eng() {
+		// Do not perform costly LTO optimizations for Eng builds.
+		if Bool(lto.Properties.Lto_O0) || ctx.Config().Eng() {
 			ltoLdFlags = append(ltoLdFlags, "-Wl,--lto-O0")
 		}