diff --git a/litex/soc/software/common.mak b/litex/soc/software/common.mak
index a2d90b96d..6d8486b5a 100644
--- a/litex/soc/software/common.mak
+++ b/litex/soc/software/common.mak
@@ -52,10 +52,11 @@ INCLUDES = -I$(PICOLIBC_DIRECTORY)/newlib/libc/tinystdio \
            -I$(BUILDINC_DIRECTORY) \
            -I$(BUILDINC_DIRECTORY)/../libc \
            -I$(CPU_DIRECTORY)
+PICOLIBC_SPECS = --specs=$(BUILDINC_DIRECTORY)/../libc/picolibc.specs -DPICOLIBC_INTEGER_PRINTF_SCANF
 COMMONFLAGS = $(DEPFLAGS) -Os $(CPUFLAGS) -g3 -fomit-frame-pointer -Wall -fno-builtin -fno-stack-protector -flto $(INCLUDES)
 CFLAGS = $(COMMONFLAGS) -fexceptions -Wstrict-prototypes -Wold-style-definition -Wmissing-prototypes
 CXXFLAGS = $(COMMONFLAGS) -std=c++11 -I$(SOC_DIRECTORY)/software/include/basec++ -fexceptions -fno-rtti -ffreestanding
-LDFLAGS = -nostdlib -nodefaultlibs -Wl,--no-dynamic-linker -Wl,--build-id=none $(CFLAGS) -L$(BUILDINC_DIRECTORY)
+LDFLAGS = -nostdlib -nodefaultlibs -Wl,--no-dynamic-linker -Wl,--build-id=none $(CFLAGS) -L$(BUILDINC_DIRECTORY) $(PICOLIBC_SPECS)
 
 define compilexx
 $(CX) -c $(CXXFLAGS) $(1) $< -o $@
diff --git a/litex/soc/software/libc/Makefile b/litex/soc/software/libc/Makefile
index ab55e33c8..d57587649 100644
--- a/litex/soc/software/libc/Makefile
+++ b/litex/soc/software/libc/Makefile
@@ -1,7 +1,7 @@
 include ../include/generated/variables.mak
 include $(SOC_DIRECTORY)/software/common.mak
 
-all: libc.a iob.c.o missing.c.o exchange.c.o arc4random.c.o
+all: libc.a iob.c.o missing.c.o
 
 CPUFAMILY=
 
@@ -35,8 +35,8 @@ cpu = '$(CPU)'
 endian = '$(CPUENDIANNESS)'
 
 [built-in options]
-c_args = [ '-DPRINTF_LEVEL=1', $(foreach flag,$(filter-out $(DEPFLAGS),$(CFLAGS)),'$(flag)',) ]
-c_link_args = [ '-DPRINTF_LEVEL=1', $(foreach flag,$(LDFLAGS),'$(flag)',) ]
+c_args = [ $(foreach flag,$(filter-out $(DEPFLAGS) -flto,$(CFLAGS)),'$(flag)',) ]
+c_link_args = [ $(foreach flag,$(filter-out -flto,$(LDFLAGS)),'$(flag)',) ]
 endef
 
 export CROSSFILE
@@ -68,11 +68,3 @@ missing.c.o: $(LIBC_DIRECTORY)/missing.c
 	$(compile)
 	$(AR) csr libc.a $@
 
-exchange.c.o: $(PICOLIBC_DIRECTORY)/newlib/libc/tinystdio/exchange.c
-	$(call compile,-fno-lto)
-	$(AR) csr libc.a $@
-
-arc4random.c.o: $(PICOLIBC_DIRECTORY)/newlib/libc/stdlib/arc4random.c
-	$(call compile,-fno-lto)
-	$(AR) csr libc.a $@
-