[uClibc] Dynamic libstdc++ still crashes on PowerPC with 0.9.22

[Richard_Theil at dadebehring.com]

I built the toolchain for uclibc 0.9.22 and ran some checks on whether
the previous problems have disappeared. ldso seems to work nicely
now, but a dynamically linked libstdc++ still crashes exactly as before
(and the static-linked programs run just as well).

The point of the crash is exactly reproducible in gdb on a Powerbook
G3 (PPC750) (but alas, I can't devote the time to take the whole load
process apart ...) - it happens on the sixth entry of
std::locale::operator=(std::locale const&) at the second lwarx operation.

For the first 5 calls, r31 contains reasonable values, on the 6th call,
it reliably contains $00000008 (which it loads before), causing a
SIGSEGV. Could that be a problem with loader-provided
pre-initialized data (?!).
 
Any hint on how to sort that out would of course be appreciated :)

Rich

Logs for the curious:

Program received signal SIGSEGV, Segmentation fault.
0x30048e20 in std::locale::operator=(std::locale const&) ()
   from /home/rich/target/lib/libstdc++.so.5
(gdb) bt
#0  0x30048e20 in std::locale::operator=(std::locale const&) ()
   from /home/rich/target/lib/libstdc++.so.5
#1  0x3004464c in std::ios_base::_M_init() ()
   from /home/rich/target/lib/libstdc++.so.5
#2  0x30043964 in std::basic_ios<char, std::char_traits<char> 
>::init(std::basic_streambuf<char, std::char_traits<char> >*) ()
   from /home/rich/target/lib/libstdc++.so.5
#3  0x30044240 in std::ios_base::Init::_S_ios_create(bool) ()
   from /home/rich/target/lib/libstdc++.so.5
#4  0x30044384 in std::ios_base::Init::Init() ()
   from /home/rich/target/lib/libstdc++.so.5
#5  0x30043dd0 in std::iostream::~iostream() ()
   from /home/rich/target/lib/libstdc++.so.5
#6  0x30073ae8 in __cxa_dyn_string_eq ()
   from /home/rich/target/lib/libstdc++.so.5
#7  0x3003bdb0 in _SDA_BASE_ () from /home/rich/target/lib/libstdc++.so.5
#8  0x30002958 in _dl_parse_copy_information () from /lib/ld-uClibc.so.0
#9  0x30001d4c in _dl_parse_copy_information () from /lib/ld-uClibc.so.0
#10 0x30000d3c in _dl_boot () from /lib/ld-uClibc.so.0

(gdb) disas
Dump of assembler code for function _ZNSt6localeaSERKS_:
0x30048df0 <_ZNSt6localeaSERKS_>:       stwu    r1,-32(r1)
0x30048df4 <_ZNSt6localeaSERKS_+4>:     mflr    r0
0x30048df8 <_ZNSt6localeaSERKS_+8>:     stmw    r29,20(r1)
0x30048dfc <_ZNSt6localeaSERKS_+12>:    stw     r0,36(r1)
0x30048e00 <_ZNSt6localeaSERKS_+16>:    mr      r29,r4
0x30048e04 <_ZNSt6localeaSERKS_+20>:    mr      r30,r3
0x30048e08 <_ZNSt6localeaSERKS_+24>:    lwz     r0,0(r4)
0x30048e0c <_ZNSt6localeaSERKS_+28>:    lwarx   r9,r0,r0
0x30048e10 <_ZNSt6localeaSERKS_+32>:    addi    r9,r9,1
0x30048e14 <_ZNSt6localeaSERKS_+36>:    stwcx.  r9,r0,r0
0x30048e18 <_ZNSt6localeaSERKS_+40>:
    bne-        0x30048e0c <_ZNSt6localeaSERKS_+28>
0x30048e1c <_ZNSt6localeaSERKS_+44>:    lwz     r31,0(r3)
0x30048e20 <_ZNSt6localeaSERKS_+48>:    lwarx   r9,r0,r31
0x30048e24 <_ZNSt6localeaSERKS_+52>:    addi    r0,r9,-1
0x30048e28 <_ZNSt6localeaSERKS_+56>:    stwcx.  r0,r0,r31
0x30048e2c <_ZNSt6localeaSERKS_+60>:
    bne-        0x30048e20 <_ZNSt6localeaSERKS_+48>
0x30048e30 <_ZNSt6localeaSERKS_+64>:    cmpwi   r9,1
0x30048e34 <_ZNSt6localeaSERKS_+68>:    cmpwi   cr7,r31,0
0x30048e38 <_ZNSt6localeaSERKS_+72>:
    bne+        0x30048e50 <_ZNSt6localeaSERKS_+96>



r0             0x30094d88       805916040
r1             0x7ffff2d0       2147480272
r2             0x0      0
r3             0x30095230       805917232
r4             0x7ffff2f8       2147480312
r5             0x10     16
r6             0x0      0
r7             0x30130f7c       806555516
r8             0x30094e08       805916168
r9             0xc      12
r10            0x3009375c       805910364
r11            0x30094d88       805916040
r12            0x3000021c       805306908
r13            0x0      0
r14            0x30005140       805327168
r15            0x30005000       805326848
r16            0x2      2
r17            0xe4     228
r18            0x300050a0       805327008
r19            0xe4     228
r20            0x30002a90       805317264
r21            0x10010e88       268504712
r22            0x30000000       805306368
r23            0x7ffff92c       2147481900
r24            0x30005140       805327168
r25            0x6      6
r26            0x0      0
r27            0x30130dd8       806555096
r28            0x300951d0       805917136
r29            0x7ffff2f8       2147480312
r30            0x30095230       805917232
r31            0x8      8
pc             0x30048e20       805604896
ps             0xd032   53298
cr             0x20000004       536870916
lr             0x3004464c       805586508
ctr            0x0      0
xer            0x0      0

0x30095230 <_ZSt3cin+108>:      0x00000008

0x30094d88 <_ZGVNSt7collateIcE2idE+5560>:       0x0000000c
0x30094d8c <_ZGVNSt7collateIcE2idE+5564>:       0x30094e08
0x30094d90 <_ZGVNSt7collateIcE2idE+5568>:       0x0000000e
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