[build] Use CC as a linker

Signed-off-by: Pedro Falcato <[email protected]>

Author: heatd

arch/arm/rules.mk

@@ -325,7 +325,7 @@ ARCH_COMPILEFLAGS += $(ARCH_$(ARCH)_COMPILEFLAGS)
 GLOBAL_COMPILEFLAGS += $(THUMBINTERWORK)
 
 # set the max page size to something more reasonable (defaults to 64K or above)
-ARCH_LDFLAGS += -z max-page-size=4096
+ARCH_LDFLAGS += -Wl,-z,max-page-size=4096
 
 # find the direct path to libgcc.a for our particular multilib variant
 LIBGCC := $(shell $(TOOLCHAIN_PREFIX)gcc $(GLOBAL_COMPILEFLAGS) $(ARCH_COMPILEFLAGS) $(THUMBCFLAGS) -print-libgcc-file-name)

arch/arm/toolchain.mk

@@ -111,7 +111,7 @@ ARCH_arm_COMPILEFLAGS += -march=armv7-r
 ARCH_arm_COMPILEFLAGS += -mcpu=$(ARM_CPU)
 ARCH_arm_COMPILEFLAGS += -mbig-endian
 ARCH_arm_COMPILEFLAGS += -mfpu=vfpv3-d16 -mfloat-abi=hard
-GLOBAL_MODULE_LDFLAGS += -EB
+GLOBAL_MODULE_LDFLAGS += -Wl,-EB
 endif
 ifeq ($(ARM_CPU),armemu)
 ARCH_arm_COMPILEFLAGS += -march=armv7-a

arch/arm64/rules.mk

@@ -94,7 +94,7 @@ $(info TOOLCHAIN_PREFIX = $(TOOLCHAIN_PREFIX))
 ARCH_COMPILEFLAGS += $(ARCH_$(ARCH)_COMPILEFLAGS)
 ARCH_COMPILEFLAGS += -fno-omit-frame-pointer
 
-ARCH_LDFLAGS += -z max-page-size=4096
+ARCH_LDFLAGS += -Wl,-z,max-page-size=4096
 
 LIBGCC := $(shell $(TOOLCHAIN_PREFIX)gcc $(GLOBAL_COMPILEFLAGS) $(ARCH_COMPILEFLAGS) -print-libgcc-file-name)
 

arch/microblaze/rules.mk

@@ -30,8 +30,8 @@ LITTLE_ENDIAN ?= 0
 
 ifneq ($(LITTLE_ENDIAN),0)
 ARCH_COMPILEFLAGS += -mlittle-endian
-ARCH_LDFLAGS += -EL
-GLOBAL_MODULE_LDFLAGS += -EL
+ARCH_LDFLAGS += -Wl,-EL
+GLOBAL_MODULE_LDFLAGS += -Wl,-EL
 endif
 
 LIBGCC := $(shell $(TOOLCHAIN_PREFIX)gcc $(GLOBAL_COMPILEFLAGS) $(ARCH_COMPILEFLAGS) $(GLOBAL_COMPILEFLAGS) -print-libgcc-file-name)
@@ -42,7 +42,9 @@ cc-option = $(shell if test -z "`$(1) $(2) -S -o /dev/null -xc /dev/null 2>&1`";
 
 ARCH_OPTFLAGS := -O2
 
-ARCH_LDFLAGS += -relax
+# -L$(BUILDDIR) is needed so the linker can find the xilinx.ld it wants
+ARCH_LDFLAGS += -Wl,-relax -L$(BUILDDIR)
+GLOBAL_MODULE_LDFLAGS += -L$(BUILDDIR)
 
 KERNEL_BASE ?= $(MEMBASE)
 KERNEL_LOAD_OFFSET ?= 0
@@ -54,9 +56,11 @@ GLOBAL_DEFINES += \
 
 # potentially generated files that should be cleaned out with clean make rule
 GENERATED += \
-	$(BUILDDIR)/linker.ld
+	$(BUILDDIR)/linker.ld \
+	$(BUILDDIR)/xilinx.ld
+
+# Rules for generating the linker scripts
 
-# rules for generating the linker
 $(BUILDDIR)/linker.ld: $(LOCAL_DIR)/linker.ld $(wildcard arch/*.ld) linkerscript.phony
 	@echo generating $@
 	@$(MKDIR)
@@ -66,6 +70,16 @@ $(BUILDDIR)/linker.ld: $(LOCAL_DIR)/linker.ld $(wildcard arch/*.ld) linkerscript
 linkerscript.phony:
 .PHONY: linkerscript.phony
 
-LINKER_SCRIPT += $(BUILDDIR)/linker.ld
+# Note: This is all messy and horrible
+# GCC needs to find a xilinx.ld, we usually pass the LINKER_SCRIPT as -dT (default linker script), and so
+# does GCC when it can't find a -T option in the command line
+# Because of that, we pass the actual linker script as linker.ld
+
+$(BUILDDIR)/xilinx.ld:
+	$(NOECHO)touch $@
+
+EXTRA_LINKER_SCRIPTS += $(BUILDDIR)/linker.ld
+
+LINKER_SCRIPT += $(BUILDDIR)/xilinx.ld
 
 include make/module.mk

arch/mips/rules.mk

@@ -32,8 +32,8 @@ LITTLE_ENDIAN ?= 0
 ifneq ($(LITTLE_ENDIAN),0)
 ARCH_COMPILEFLAGS += -EL
 ARCH_ASFLAGS += -EL
-ARCH_LDFLAGS += -EL
-GLOBAL_MODULE_LDFLAGS += -EL
+ARCH_LDFLAGS += -Wl,-EL
+GLOBAL_MODULE_LDFLAGS += -Wl,-EL
 endif
 
 ARCH_COMPILEFLAGS += -mno-gpopt

arch/or1k/rules.mk

@@ -25,7 +25,7 @@ cc-option = $(shell if test -z "`$(1) $(2) -S -o /dev/null -xc /dev/null 2>&1`";
 
 ARCH_OPTFLAGS := -O2
 
-ARCH_LDFLAGS += -relax
+ARCH_LDFLAGS += -Wl,-relax
 
 LIBGCC := $(shell $(TOOLCHAIN_PREFIX)gcc $(GLOBAL_COMPILEFLAGS) $(ARCH_COMPILEFLAGS) -print-libgcc-file-name)
 $(info LIBGCC = $(LIBGCC))

arch/riscv/rules.mk

@@ -137,12 +137,12 @@ endif
 ifeq ($(SUBARCH),32)
 ARCH_COMPILEFLAGS := -march=rv32imac -mabi=ilp32
 # override machine for ld -r
-GLOBAL_MODULE_LDFLAGS += -m elf32lriscv
+GLOBAL_MODULE_LDFLAGS += -Wl,-m,elf32lriscv
 else ifeq ($(SUBARCH),64)
 GLOBAL_DEFINES += IS_64BIT=1
 ARCH_COMPILEFLAGS := -march=rv64imac -mabi=lp64 -mcmodel=medany
 # override machine for ld -r
-GLOBAL_MODULE_LDFLAGS += -m elf64lriscv
+GLOBAL_MODULE_LDFLAGS += -Wl,-m,elf64lriscv
 else
 $(error SUBARCH not set or set to something unknown)
 endif
@@ -184,7 +184,7 @@ LINKER_SCRIPT += $(BUILDDIR)/linker-twosegment.ld
 # a paged sytem would.
 # NOTE: 8 seems to be about as far as you can go. experienced some extra stuffed words
 # when using 4.
-ARCH_LDFLAGS += -z max-page-size=8
+ARCH_LDFLAGS += -Wl,-z,max-page-size=8
 else
 GLOBAL_DEFINES += ARCH_RISCV_TWOSEGMENT=0
 LINKER_SCRIPT += $(BUILDDIR)/linker-onesegment.ld

arch/x86/rules.mk

@@ -95,7 +95,7 @@ GLOBAL_CFLAGS += $(call cc-option,$(CC),-fno-stack-protector,)
 ARCH_COMPILEFLAGS += -fasynchronous-unwind-tables
 ARCH_COMPILEFLAGS += -gdwarf-2
 ARCH_COMPILEFLAGS += -fno-pic
-ARCH_LDFLAGS += -z max-page-size=4096
+ARCH_LDFLAGS += -Wl,-z,max-page-size=4096
 
 ifeq ($(SUBARCH),x86-64)
 ARCH_COMPILEFLAGS += -fno-stack-protector

engine.mk

@@ -214,7 +214,7 @@ endif
 # default to no ccache
 CCACHE ?=
 CC := $(CCACHE) $(TOOLCHAIN_PREFIX)gcc
-LD := $(TOOLCHAIN_PREFIX)ld
+LD := $(TOOLCHAIN_PREFIX)gcc
 OBJDUMP := $(TOOLCHAIN_PREFIX)objdump
 OBJCOPY := $(TOOLCHAIN_PREFIX)objcopy
 CPPFILT := $(TOOLCHAIN_PREFIX)c++filt

make/build.mk

@@ -1,9 +1,12 @@
 # use linker garbage collection, if requested
 ifeq ($(WITH_LINKER_GC),1)
 GLOBAL_COMPILEFLAGS += -ffunction-sections -fdata-sections
-GLOBAL_LDFLAGS += --gc-sections
+GLOBAL_LDFLAGS += -Wl,--gc-sections
 endif
 
+GLOBAL_LDFLAGS += -static -ffreestanding -nostartfiles -nostdlib -fuse-ld=bfd
+GLOBAL_MODULE_LDFLAGS += -static -ffreestanding -nostartfiles -nostdlib -fuse-ld=bfd
+
 ifneq (,$(EXTRA_BUILDRULES))
 -include $(EXTRA_BUILDRULES)
 endif
@@ -19,12 +22,14 @@ $(OUTELF).hex: $(OUTELF)
 	$(info generating hex file: $@)
 	$(NOECHO)$(OBJCOPY) -O ihex $< $@
 
+comma = ,
+
 $(OUTELF): $(ALLMODULE_OBJS) $(EXTRA_OBJS) $(LINKER_SCRIPT) $(EXTRA_LINKER_SCRIPTS)
 	$(info linking $@)
 	$(NOECHO)$(SIZE) -t --common $(sort $(ALLMODULE_OBJS)) $(EXTRA_OBJS)
-	$(NOECHO)$(LD) $(GLOBAL_LDFLAGS) $(ARCH_LDFLAGS) -dT $(LINKER_SCRIPT) \
+	$(NOECHO)$(LD) $(GLOBAL_LDFLAGS) $(ARCH_LDFLAGS) -Wl,--verbose -v -Wl,-dT$(LINKER_SCRIPT) \
 		$(addprefix -T,$(EXTRA_LINKER_SCRIPTS)) \
-		$(ALLMODULE_OBJS) $(EXTRA_OBJS) $(LIBGCC) -Map=$(OUTELF).map -o $@
+		$(ALLMODULE_OBJS) $(EXTRA_OBJS) $(LIBGCC) -Wl,-Map=$(OUTELF).map -o $@
 
 $(OUTELF).sym: $(OUTELF)
 	$(info generating symbols: $@)