toolchain: gccgo: fix building gccgo compiler

Fixes FS#1498.  "gccgo -static" can fail for missing linker flag
-lgcc_eh caused by patch 850-use_shared_libgcc.patch

Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

2 files changed, 248 insertions, 0 deletions

diff --git a/toolchain/gcc/patches/7.3.0/931-libffi-fix-MIPS-softfloat-build-issue.patch b/toolchain/gcc/patches/7.3.0/931-libffi-fix-MIPS-softfloat-build-issue.patch
new file mode 100644
index 0000000000..9d436efc18
--- /dev/null
+++ b/toolchain/gcc/patches/7.3.0/931-libffi-fix-MIPS-softfloat-build-issue.patch
@@ -0,0 +1,175 @@
+From c0c62fa4256f805389f16ebfc4a60cf789129b50 Mon Sep 17 00:00:00 2001
+From: BangLang Huang <banglang.huang@foxmail.com>
+Date: Wed, 9 Nov 2016 10:36:49 +0800
+Subject: [PATCH] libffi: fix MIPS softfloat build issue
+
+Backported from github.com/libffi/libffi#272
+
+Signed-off-by: BangLang Huang <banglang.huang@foxmail.com>
+Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>
+---
+ libffi/src/mips/n32.S | 17 +++++++++++++++++
+ libffi/src/mips/o32.S | 17 +++++++++++++++++
+ 2 files changed, 34 insertions(+)
+
+diff --git a/libffi/src/mips/n32.S b/libffi/src/mips/n32.S
+index c6985d30a6f..8f25994773c 100644
+--- a/libffi/src/mips/n32.S
++++ b/libffi/src/mips/n32.S
+@@ -107,6 +107,16 @@ loadregs:
+ 
+ 	REG_L	t6, 3*FFI_SIZEOF_ARG($fp)  # load the flags word into t6.
+ 
++#ifdef __mips_soft_float
++	REG_L	a0, 0*FFI_SIZEOF_ARG(t9)
++	REG_L	a1, 1*FFI_SIZEOF_ARG(t9)
++	REG_L	a2, 2*FFI_SIZEOF_ARG(t9)
++	REG_L	a3, 3*FFI_SIZEOF_ARG(t9)
++	REG_L	a4, 4*FFI_SIZEOF_ARG(t9)
++	REG_L	a5, 5*FFI_SIZEOF_ARG(t9)
++	REG_L	a6, 6*FFI_SIZEOF_ARG(t9)
++	REG_L	a7, 7*FFI_SIZEOF_ARG(t9)
++#else
+ 	and	t4, t6, ((1<<FFI_FLAG_BITS)-1)
+ 	REG_L	a0, 0*FFI_SIZEOF_ARG(t9)
+ 	beqz	t4, arg1_next
+@@ -193,6 +203,7 @@ arg7_next:
+ arg8_doublep:	
+  	l.d	$f19, 7*FFI_SIZEOF_ARG(t9)	
+ arg8_next:	
++#endif
+ 
+ callit:		
+ 	# Load the function pointer
+@@ -214,6 +225,7 @@ retint:
+ 	b	epilogue
+ 
+ retfloat:
++#ifndef __mips_soft_float
+ 	bne     t6, FFI_TYPE_FLOAT, retdouble
+ 	jal	t9
+ 	REG_L	t4, 4*FFI_SIZEOF_ARG($fp)
+@@ -272,6 +284,7 @@ retstruct_f_d:
+ 	s.s	$f0, 0(t4)
+ 	s.d	$f2, 8(t4)
+ 	b	epilogue
++#endif
+ 
+ retstruct_d_soft:
+ 	bne	t6, FFI_TYPE_STRUCT_D_SOFT, retstruct_f_soft
+@@ -429,6 +442,7 @@ ffi_closure_N32:
+ 	REG_S	a6, A6_OFF2($sp)
+ 	REG_S	a7, A7_OFF2($sp)
+ 
++#ifndef __mips_soft_float
+ 	# Store all possible float/double registers.
+ 	s.d	$f12, F12_OFF2($sp)
+ 	s.d	$f13, F13_OFF2($sp)
+@@ -438,6 +452,7 @@ ffi_closure_N32:
+ 	s.d	$f17, F17_OFF2($sp)
+ 	s.d	$f18, F18_OFF2($sp)
+ 	s.d	$f19, F19_OFF2($sp)
++#endif
+ 
+ 	# Call ffi_closure_mips_inner_N32 to do the real work.
+ 	LA	t9, ffi_closure_mips_inner_N32
+@@ -458,6 +473,7 @@ cls_retint:
+ 	b	cls_epilogue
+ 
+ cls_retfloat:
++#ifndef __mips_soft_float
+ 	bne     v0, FFI_TYPE_FLOAT, cls_retdouble
+ 	l.s	$f0, V0_OFF2($sp)
+ 	b	cls_epilogue
+@@ -500,6 +516,7 @@ cls_retstruct_f_d:
+ 	l.s	$f0, V0_OFF2($sp)
+ 	l.d	$f2, V1_OFF2($sp)
+ 	b	cls_epilogue
++#endif
+ 	
+ cls_retstruct_small2:	
+ 	REG_L	v0, V0_OFF2($sp)
+diff --git a/libffi/src/mips/o32.S b/libffi/src/mips/o32.S
+index eb279813a76..1aff4b14814 100644
+--- a/libffi/src/mips/o32.S
++++ b/libffi/src/mips/o32.S
+@@ -82,13 +82,16 @@ sixteen:
+ 		
+ 	ADDU	$sp, 4 * FFI_SIZEOF_ARG		# adjust $sp to new args
+ 
++#ifndef __mips_soft_float
+ 	bnez	t0, pass_d			# make it quick for int
++#endif
+ 	REG_L	a0, 0*FFI_SIZEOF_ARG($sp)	# just go ahead and load the
+ 	REG_L	a1, 1*FFI_SIZEOF_ARG($sp)	# four regs.
+ 	REG_L	a2, 2*FFI_SIZEOF_ARG($sp)
+ 	REG_L	a3, 3*FFI_SIZEOF_ARG($sp)
+ 	b	call_it
+ 
++#ifndef __mips_soft_float
+ pass_d:
+ 	bne	t0, FFI_ARGS_D, pass_f
+ 	l.d	$f12, 0*FFI_SIZEOF_ARG($sp)	# load $fp regs from args
+@@ -130,6 +133,7 @@ pass_f_d:
+  #	bne	t0, FFI_ARGS_F_D, call_it
+ 	l.s	$f12, 0*FFI_SIZEOF_ARG($sp)	# load $fp regs from args
+ 	l.d	$f14, 2*FFI_SIZEOF_ARG($sp)	# passing double and float
++#endif
+ 
+ call_it:	
+ 	# Load the function pointer
+@@ -158,14 +162,23 @@ retfloat:
+ 	bne     t2, FFI_TYPE_FLOAT, retdouble
+ 	jalr	t9
+ 	REG_L	t0, SIZEOF_FRAME + 4*FFI_SIZEOF_ARG($fp)
++#ifndef __mips_soft_float
+ 	s.s	$f0, 0(t0)
++#else
++	REG_S v0, 0(t0)
++#endif
+ 	b	epilogue
+ 
+ retdouble:	
+ 	bne	t2, FFI_TYPE_DOUBLE, noretval
+ 	jalr	t9
+ 	REG_L	t0, SIZEOF_FRAME + 4*FFI_SIZEOF_ARG($fp)
++#ifndef __mips_soft_float
+ 	s.d	$f0, 0(t0)
++#else
++	REG_S v1, 4(t0)
++	REG_S v0, 0(t0)
++#endif
+ 	b	epilogue
+ 	
+ noretval:	
+@@ -261,9 +274,11 @@ $LCFI7:
+ 	li	$13, 1		# FFI_O32
+ 	bne	$16, $13, 1f	# Skip fp save if FFI_O32_SOFT_FLOAT
+ 	
++#ifndef __mips_soft_float
+ 	# Store all possible float/double registers.
+ 	s.d	$f12, FA_0_0_OFF2($fp)
+ 	s.d	$f14, FA_1_0_OFF2($fp)
++#endif
+ 1:	
+ 	# Call ffi_closure_mips_inner_O32 to do the work.
+ 	la	t9, ffi_closure_mips_inner_O32
+@@ -281,6 +296,7 @@ $LCFI7:
+ 	li	$13, 1		# FFI_O32
+ 	bne	$16, $13, 1f	# Skip fp restore if FFI_O32_SOFT_FLOAT
+ 
++#ifndef __mips_soft_float
+ 	li	$9, FFI_TYPE_FLOAT
+ 	l.s	$f0, V0_OFF2($fp)
+ 	beq	$8, $9, closure_done
+@@ -288,6 +304,7 @@ $LCFI7:
+ 	li	$9, FFI_TYPE_DOUBLE
+ 	l.d	$f0, V0_OFF2($fp)
+ 	beq	$8, $9, closure_done
++#endif
+ 1:	
+ 	REG_L	$3, V1_OFF2($fp)
+ 	REG_L	$2, V0_OFF2($fp)
+-- 
+2.16.3
+
diff --git a/toolchain/gcc/patches/7.3.0/960-gotools-fix-compilation-when-making-cross-compiler.patch b/toolchain/gcc/patches/7.3.0/960-gotools-fix-compilation-when-making-cross-compiler.patch
new file mode 100644
index 0000000000..556fa16473
--- /dev/null
+++ b/toolchain/gcc/patches/7.3.0/960-gotools-fix-compilation-when-making-cross-compiler.patch
@@ -0,0 +1,73 @@
+From dda6b050cd74a352670787a294596a9c56c21327 Mon Sep 17 00:00:00 2001
+From: Yousong Zhou <yszhou4tech@gmail.com>
+Date: Fri, 4 May 2018 18:20:53 +0800
+Subject: [PATCH] gotools: fix compilation when making cross compiler
+
+libgo is "the runtime support library for the Go programming language.
+This library is intended for use with the Go frontend."
+
+gccgo will link target files with libgo.so which depends on libgcc_s.so.1, but
+the linker will complain that it cannot find it.  That's because shared libgcc
+is not present in the install directory yet.  libgo.so was made without problem
+because gcc will emit -lgcc_s when compiled with -shared option.  When gotools
+were being made, it was supplied with -static-libgcc thus no link option was
+provided.  Check LIBGO in gcc/go/gcc-spec.c for how gccgo make a builtin spec
+for linking with libgo.so
+
+- GccgoCrossCompilation, https://github.com/golang/go/wiki/GccgoCrossCompilation
+- Cross-building instructions, http://www.eglibc.org/archives/patches/msg00078.html
+
+When 3-pass GCC compilation is used, shared libgcc runtime libraries will be
+available after gcc pass2 completed and will meet the gotools link requirement
+at gcc pass3
+---
+ gotools/Makefile.am | 4 +++-
+ gotools/Makefile.in | 4 +++-
+ 2 files changed, 6 insertions(+), 2 deletions(-)
+
+diff --git a/gotools/Makefile.am b/gotools/Makefile.am
+index 5f3940a278b..9c22f5df103 100644
+--- a/gotools/Makefile.am
++++ b/gotools/Makefile.am
+@@ -26,6 +26,7 @@ PWD_COMMAND = $${PWDCMD-pwd}
+ STAMP = echo timestamp >
+ 
+ libgodir = ../$(target_noncanonical)/libgo
++libgccdir = ../$(target_noncanonical)/libgcc
+ LIBGODEP = $(libgodir)/libgo.la
+ 
+ if NATIVE
+@@ -38,7 +39,8 @@ endif
+ GOCFLAGS = $(CFLAGS_FOR_TARGET)
+ GOCOMPILE = $(GOCOMPILER) $(GOCFLAGS)
+ 
+-AM_LDFLAGS = -L $(libgodir) -L $(libgodir)/.libs
++AM_LDFLAGS = -L $(libgodir) -L $(libgodir)/.libs \
++	-L $(libgccdir) -L $(libgccdir)/.libs -lgcc_s
+ GOLINK = $(GOCOMPILER) $(GOCFLAGS) $(AM_GOCFLAGS) $(LDFLAGS) $(AM_LDFLAGS) -o $@
+ 
+ cmdsrcdir = $(srcdir)/../libgo/go/cmd
+diff --git a/gotools/Makefile.in b/gotools/Makefile.in
+index 4386576b011..0bdd9290e01 100644
+--- a/gotools/Makefile.in
++++ b/gotools/Makefile.in
+@@ -252,13 +252,15 @@ mkinstalldirs = $(SHELL) $(toplevel_srcdir)/mkinstalldirs
+ PWD_COMMAND = $${PWDCMD-pwd}
+ STAMP = echo timestamp >
+ libgodir = ../$(target_noncanonical)/libgo
++libgccdir = ../$(target_noncanonical)/libgcc
+ LIBGODEP = $(libgodir)/libgo.la
+ @NATIVE_FALSE@GOCOMPILER = $(GOC)
+ 
+ # Use the compiler we just built.
+ @NATIVE_TRUE@GOCOMPILER = $(GOC_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET)
+ GOCOMPILE = $(GOCOMPILER) $(GOCFLAGS)
+-AM_LDFLAGS = -L $(libgodir) -L $(libgodir)/.libs
++AM_LDFLAGS = -L $(libgodir) -L $(libgodir)/.libs \
++	-L $(libgccdir) -L $(libgccdir)/.libs -lgcc_s
+ GOLINK = $(GOCOMPILER) $(GOCFLAGS) $(AM_GOCFLAGS) $(LDFLAGS) $(AM_LDFLAGS) -o $@
+ cmdsrcdir = $(srcdir)/../libgo/go/cmd
+ go_cmd_go_files = \
+-- 
+2.16.3
+