diff --git a/Library/Homebrew/extend/os/mac/hardware.rb b/Library/Homebrew/extend/os/mac/hardware.rb
index d5765f6d62..975e308d4a 100644
--- a/Library/Homebrew/extend/os/mac/hardware.rb
+++ b/Library/Homebrew/extend/os/mac/hardware.rb
@@ -2,8 +2,6 @@ module Hardware
   def self.oldest_cpu
     if MacOS.version >= :mojave
       :nehalem
-    elsif MacOS.version >= :sierra
-      :penryn
     else
       generic_oldest_cpu
     end
diff --git a/Library/Homebrew/hardware.rb b/Library/Homebrew/hardware.rb
index 65789c1220..2611bad014 100644
--- a/Library/Homebrew/hardware.rb
+++ b/Library/Homebrew/hardware.rb
@@ -9,7 +9,6 @@ module Hardware
       OPTIMIZATION_FLAGS = {
         native:  "-march=native",
         nehalem: "-march=nehalem",
-        penryn:  "-march=penryn",
         core2:   "-march=core2",
         core:    "-march=prescott",
         armv6:   "-march=armv6",