🚀 go-pugleaf

I added -v to the CFLAGS and tried the build.  It showed me:

cd /usr6/aej/gcc-2.0/
gmake -j 1
rm -f tmplibgcc2.a
set -e; \
for name in _muldi3 _divdi3 _moddi3 _udivdi3 _umoddi3 _negdi2 _lshrdi3 _lshldi3 _ashldi3 _ashrdi3 _udivmoddi4 _cmpdi2 _ucmpdi2 _floatdidf _floatdisf _fixunsdfsi _fixunssfsi _fixunsdfdi _fixdfdi _fixunssfdi _fixsfdi _varargs _eprintf _builtin_new _builtin_New _builtin_del _bb _shtab _clear_cache _trampoline __main _exit; \
do \
  echo ${name}; \
  ./gcc -fstrength-reduce -O -I. -I. -I./config \
      -O2    -g -v -B./ -g1 -c -DL${name} \
      ./libgcc2.c -o ${name}.o; \
  if [ $? -eq 0 ] ; then true; else exit 1; fi; \
  ar rc tmplibgcc2.a ${name}.o; \
  rm -f ${name}.o; \
done
_muldi3
Reading specs from ./specs
gcc version 2.0
 ./cpp -lang-c -v -DL_muldi3 -I. -I. -I./config -undef -D__GNUC__=2 -Dns32000 -Dn16 -Dns16000 -Dns32332 -Dunix -D__ns32000__ -D__n16__ -D__ns16000__ -D__ns32332__ -D__unix__ -D__ns32000 -D__n16 -D__ns16000 -D__ns32332 -D__unix -D__OPTIMIZE__ -g -g1 ./libgcc2.c /usr/tmp/cc019540.cpp
GNU CPP version 2.0 (32000, Encore syntax)
 ./cc1 /usr/tmp/cc019540.cpp -quiet -dumpbase libgcc2.c -g -g1 -O -O2 -version -fstrength-reduce -o /usr/tmp/cc019540.s
GNU C version 2.0 (32000, Encore syntax) compiled by CC.
 as -j -o _muldi3.o /usr/tmp/cc019540.s
_divdi3
Reading specs from ./specs
gcc version 2.0
 ./cpp -lang-c -v -DL_divdi3 -I. -I. -I./config -undef -D__GNUC__=2 -Dns32000 -Dn16 -Dns16000 -Dns32332 -Dunix -D__ns32000__ -D__n16__ -D__ns16000__ -D__ns32332__ -D__unix__ -D__ns32000 -D__n16 -D__ns16000 -D__ns32332 -D__unix -D__OPTIMIZE__ -g -g1 ./libgcc2.c /usr/tmp/cc024956.cpp
GNU CPP version 2.0 (32000, Encore syntax)
 ./cc1 /usr/tmp/cc024956.cpp -quiet -dumpbase libgcc2.c -g -g1 -O -O2 -version -fstrength-reduce -o /usr/tmp/cc024956.s
GNU C version 2.0 (32000, Encore syntax) compiled by CC.
 as -j -o _divdi3.o /usr/tmp/cc024956.s
Assembler: libgcc2.c
	aline 70	: illegal branch operand
	aline 92	: Warning: Unresolved branch(es)
./gcc: _divdi3.o: No such file or directory
gmake: *** [libgcc2.a] Error 1

Compilation exited abnormally with code 1 at Wed Mar 11 08:38:09

The /usr/tmp files were, of course, removed.  I snipped the commands
out and ran them individually.  The result of:

 ./cpp -lang-c -v -DL_divdi3 -I. -I. -I./config -undef -D__GNUC__=2 -Dns32000 -Dn16 -Dns16000 -Dns32332 -Dunix -D__ns32000__ -D__n16__ -D__ns16000__ -D__ns32332__ -D__unix__ -D__ns32000 -D__n16 -D__ns16000 -D__ns32332 -D__unix -D__OPTIMIZE__ -g -g1 ./libgcc2.c /usr/tmp/cc024956.cpp

was /usr/tmp/cc024956.cpp.  I edited that file into the file below
{ with the extraneous lines removed for easier reading in the news }:

extern enum reg_class secondary_reload_class();
extern int target_flags;
enum reg_class { NO_REGS, GENERAL_REGS, FLOAT_REGS, FRAME_POINTER_REG, STACK_POINTER_REG, 
                 GEN_AND_MEM_REGS, ALL_REGS, LIM_REG_CLASSES };
extern char *output_move_double ();
extern char *output_shift_insn ();
typedef long int ptrdiff_t;
typedef long unsigned int size_t;
typedef int wchar_t;
struct longlong {long low, high;};
typedef union
{
  struct longlong s;
  long long ll;
} long_long;
extern long long __fixunssfdi (float a);
extern long long __fixunsdfdi (double a);
static inline
long long
__negdi2 (u)
     long long u;
{
  long_long w;
  long_long uu;

  uu.ll = u;

  w.s.low = -uu.s.low;
  w.s.high = -uu.s.high - ((unsigned long) w.s.low > 0);

  return w.ll;
}

unsigned long long __udivmoddi4 ();
long long
__divdi3 (u, v)
     long long u, v;
{
  int c = 0;
  long_long uu, vv;
  long long w;

  uu.ll = u;
  vv.ll = v;

  if (uu.s.high < 0)
    c = ~c,
    uu.ll = __negdi2 (uu.ll);
  if (vv.s.high < 0)
    c = ~c,
    vv.ll = __negdi2 (vv.ll);

  w = __udivmoddi4 (uu.ll, vv.ll, (unsigned long long *) 0);
  if (c)
    w = __negdi2 (w);

  return w;
}

This modified result, which I called aej.cpp, was run through:

 ./cc1 /usr/tmp/aej.cpp -quiet -dumpbase libgcc2.c -g -g1 -O -O2 -version -fstrength-reduce -o /usr/tmp/aej.s

with this result:

	.file	"aej.cpp"
gcc2_compiled.:
.text
	.def	_reg_class;	.scl	15;	.type	012;	.size	4;	.endef
	.def	_NO_REGS;	.val	0;	.scl	16;	.type	013;	.endef
	.def	_GENERAL_REGS;	.val	1;	.scl	16;	.type	013;	.endef
	.def	_FLOAT_REGS;	.val	2;	.scl	16;	.type	013;	.endef
	.def	_FRAME_POINTER_REG;	.val	3;	.scl	16;	.type	013;	.endef
	.def	_STACK_POINTER_REG;	.val	4;	.scl	16;	.type	013;	.endef
	.def	_GEN_AND_MEM_REGS;	.val	5;	.scl	16;	.type	013;	.endef
	.def	_ALL_REGS;	.val	6;	.scl	16;	.type	013;	.endef
	.def	_LIM_REG_CLASSES;	.val	7;	.scl	16;	.type	013;	.endef
	.def	.eos;	.val	4;	.scl	102;	.tag	_reg_class;	.size	4;	.endef
	.def	_ptrdiff_t;	.scl	13;	.type	04;	.endef
	.def	_size_t;	.scl	13;	.type	016;	.endef
	.def	_wchar_t;	.scl	13;	.type	04;	.endef
	.def	_longlong;	.scl	10;	.type	010;	.size	8;	.endef
	.def	_low;	.val	0;	.scl	8;	.type	04;	.endef
	.def	_high;	.val	4;	.scl	8;	.type	04;	.endef
	.def	.eos;	.val	8;	.scl	102;	.tag	_longlong;	.size	8;	.endef
	.def	_.0fake;	.scl	12;	.type	011;	.size	8;	.endef
	.def	_s;	.val	0;	.scl	11;	.tag	_longlong;	.size	8;	.type	010;	.endef
	.def	_ll;	.val	0;	.scl	11;	.type	00;	.endef
	.def	.eos;	.val	8;	.scl	102;	.tag	_.0fake;	.size	8;	.endef
	.def	_long_long;	.scl	13;	.tag	_.0fake;	.size	8;	.type	011;	.endef
	.align 16
	.def	___divdi3;	.val	___divdi3;	.scl	2;	.type	040;	.endef
.globl ___divdi3
___divdi3:
	enter [r3,r4,r6,r7],24
	.def	.bf;	.val	.;	.scl	101;	.line	0;	.endef
	.def	_u;	.val	8;	.scl	9;	.type	00;	.endef
	.def	_v;	.val	16;	.scl	9;	.type	00;	.endef
	movqd $0,r4
	movd 8(fp),-8(fp)
	movd 12(fp),-4(fp)
	movd 16(fp),r2
	movd 20(fp),r3
	cmpqd $0,-4(fp)
	ble .L3
	movqd $-1,r4
	negd -8(fp),r0
	movd r0,r6
	negd -4(fp),r1
	cmpqd $0,r0
	sned r0
	movd r1,r7
	subd r0,r7
	movd r6,-8(fp)
	movd r7,-4(fp)
.L3:
	cmpqd $0,r3
	ble .L5
	comd r4,r4
	negd r2,r0
	movd r0,-16(fp)
	negd r3,r1
	cmpqd $0,r0
	sned r0
	subd r0,r1
	movd r1,-12(fp)
	movd -16(fp),r2
	movd -12(fp),r3
.L5:
	movqd $0,tos
	movd r3,tos
	movd r2,tos
	movd -4(fp),tos
	movd -8(fp),tos
	bsr $___udivmoddi4
	movd r0,r2
	movd r1,r3
	adjspd $-20
	cmpqd $0,r4
	beq .L7
	negd r2,r0
	movd r0,-24(fp)
	negd r3,r1
	cmpqd $0,r0
	sned r0
	subd r0,r1
	movd r1,-20(fp)
	movd -24(fp),r2
	movd -20(fp),r3
.L7:
	movd r2,r0
	movd r3,r1
	.def	.ef;	.val	.;	.scl	101;	.line	1;	.endef
	exit [r7,r6,r4,r3]
	ret 0
	.def	___divdi3;	.val	.;	.scl	-1;	.endef


{ By the way, the ONLY difference between the results of using the
  adulterated { blanks-removed } cpp output and the virgin one was a
  different .file line in the .s file. }

The final command:

 as -j -o _divdi3.o /usr/tmp/aej.s

resulted in the same error messages as the make, illegal branch on
line 70.

I must confess to ignorance of the specific reason why that branch is
bothering as.