Cleanup debug code and allow empty input.

Signed-off-by: Pan Li <pan2.li@intel.com>

Makefile.in

@@ -93,25 +93,25 @@ GDB_NATIVE_FLAGS := $(GDB_NATIVE_FLAGS_EXTRA)
 GLIBC_TARGET_FLAGS := $(GLIBC_TARGET_FLAGS_EXTRA)
 GLIBC_CC_FOR_TARGET ?= $(LINUX_TUPLE)-gcc
 GLIBC_CXX_FOR_TARGET ?= $(LINUX_TUPLE)-g++
-GLIBC_TARGET_BOARDS ?= $(shell set -x && $(srcdir)/scripts/generate_target_board \
+GLIBC_TARGET_BOARDS ?= $(shell $(srcdir)/scripts/generate_target_board \
   --sim-name riscv-sim \
   --cmodel $(shell echo @cmodel@ | cut -d '=' -f2) \
   --build-arch-abi $(GLIBC_MULTILIB_NAMES) \
-  --extra-test-arch-abi-flags-list $(subst ;,\;,$(EXTRA_MULTILIB_TEST)))
+  --extra-test-arch-abi-flags-list "$(subst ;,\;,$(EXTRA_MULTILIB_TEST))")
 
 NEWLIB_CC_FOR_TARGET ?= $(NEWLIB_TUPLE)-gcc
 NEWLIB_CXX_FOR_TARGET ?= $(NEWLIB_TUPLE)-g++
-NEWLIB_TARGET_BOARDS ?= $(shell set -x && $(srcdir)/scripts/generate_target_board \
+NEWLIB_TARGET_BOARDS ?= $(shell $(srcdir)/scripts/generate_target_board \
   --sim-name riscv-sim \
   --cmodel $(shell echo @cmodel@ | cut -d '=' -f2) \
   --build-arch-abi $(NEWLIB_MULTILIB_NAMES) \
-  --extra-test-arch-abi-flags-list $(subst ;,\;,$(EXTRA_MULTILIB_TEST)))
+  --extra-test-arch-abi-flags-list "$(subst ;,\;,$(EXTRA_MULTILIB_TEST))")
 
-NEWLIB_NANO_TARGET_BOARDS ?= $(shell set -x && $(srcdir)/scripts/generate_target_board \
+NEWLIB_NANO_TARGET_BOARDS ?= $(shell $(srcdir)/scripts/generate_target_board \
   --sim-name riscv-sim-nano \
   --cmodel $(shell echo @cmodel@ | cut -d '=' -f2) \
   --build-arch-abi $(NEWLIB_MULTILIB_NAMES) \
-  --extra-test-arch-abi-flags-list $(subst ;,\;,$(EXTRA_MULTILIB_TEST)))
+  --extra-test-arch-abi-flags-list "$(subst ;,\;,$(EXTRA_MULTILIB_TEST))")
 NEWLIB_CC_FOR_MULTILIB_INFO := $(NEWLIB_CC_FOR_TARGET)
 
 MUSL_TARGET_FLAGS := $(MUSL_TARGET_FLAGS_EXTRA)