diff --git a/utils/buildit/GNUmakefile b/utils/buildit/GNUmakefile
index a024c1e..400d97a 100644
--- a/utils/buildit/GNUmakefile
+++ b/utils/buildit/GNUmakefile
@@ -41,6 +41,13 @@
 LLVM_ASSERTIONS := no
 endif
 
+# Default is optimized build.
+ifeq ($(LLVM_DEBUG),1)
+LLVM_OPTIMIZED := no
+else
+LLVM_OPTIMIZED := yes
+endif
+
 ifndef RC_ProjectSourceVersion
 RC_ProjectSourceVersion = 9999
 endif
@@ -54,7 +61,7 @@
 	  $(SRC)/build_llvm "$(RC_ARCHS)" "$(TARGETS)" \
 	    $(SRC) $(PREFIX) $(DSTROOT) $(SYMROOT) \
 	    $(RC_ProjectSourceVersion) $(RC_ProjectSourceSubversion) \
-	    $(LLVM_ASSERTIONS)
+	    $(LLVM_ASSERTIONS) $(LLVM_OPTIMIZED)
 
 # installhdrs does nothing, because the headers aren't useful until
 # the compiler is installed.
diff --git a/utils/buildit/build_llvm b/utils/buildit/build_llvm
index ecef40f..90a2d96 100755
--- a/utils/buildit/build_llvm
+++ b/utils/buildit/build_llvm
@@ -44,6 +44,10 @@
 # enabled in the LLVM libs/tools.
 LLVM_ASSERTIONS="$9"
 
+# The tenth parameter is a yes/no that indicates whether this is an optimized
+# build.
+LLVM_OPTIMIZED="${10}"
+
 # The current working directory is where the build will happen. It may already
 # contain a partial result of an interrupted build, in which case this script
 # will continue where it left off.
@@ -55,19 +59,6 @@
 # If the user has CC set in their environment unset it now
 unset CC
 
-# The B&I build srcript (~rc/bin/buildit) accepts an '-othercflags' command-line
-# flag, and captures the argument to that flag in $RC_NONARCH_CFLAGS (and
-# mysteriously prepends '-pipe' thereto). We will allow this to override the
-# default $CFLAGS and $CXXFLAGS.
-
-if [ "x$LLVM_DEBUG" == "x" ]; then
-    CFLAGS="-g -O2 ${RC_NONARCH_CFLAGS/-pipe/}"
-    OPTIMIZE_OPTS="ENABLE_OPTIMIZED=1"
-else
-    CFLAGS="-g"
-    OPTIMIZE_OPTS=
-fi
-
 ################################################################################
 # Run the build.
 
@@ -85,7 +76,9 @@
 
 if [ \! -f Makefile.config ]; then
     $SRC_DIR/llvm/configure --prefix=$DEST_DIR$DEST_ROOT \
-        --enable-targets=x86,powerpc,cbe --enable-assertions=$LLVM_ASSERTIONS \
+        --enable-targets=x86,powerpc,cbe \
+        --enable-assertions=$LLVM_ASSERTIONS \
+        --enable-optimized=$LLVM_OPTIMIZED \
         || exit 1
 fi