AArch64: Backtracing broken on PAC enabled systems

On Fedora 33, all distro provided applications are built with -mbranch-protection=standard, causing them to built with PAC protection.

When this is run on a system with PAC support, OpenJDK is unable to backtrace across native functions:

pns() called from init_globals():

    Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
    V [libjvm.so+0xe26fe4] init_globals()+0x10
    C 0x006ffffff74750c4
    C 0x0042fffff6a7f84c
    C 0x0037fffff7fa0954
    C 0x0030fffff7fa4540
    C 0x0078fffff7d980c8


pns() called from pd_hotspot_signal_handler():

"Executing pns"
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x1592534] PosixSignals::pd_hotspot_signal_handler(int, siginfo_t*, ucontext_t*, JavaThread*)+0x0
C 0x0006fffff7ffc80c
j java.lang.String.indexOf(II)I+1 java.base@16.0.1
j java.lang.String.indexOf(I)I+3 java.base@16.0.1
j java.util.StringTokenizer.skipDelimiters(I)I+61 java.base@16.0.1
j java.util.StringTokenizer.countTokens()I+17 java.base@16.0.1
j sun.util.cldr.CLDRLocaleProviderAdapter.createLanguageTagSet(Ljava/lang/String;)Ljava/util/Set;+92 java.base@16.0.1
j sun.util.locale.provider.JRELocaleProviderAdapter.getLanguageTagSet(Ljava/lang/String;)Ljava/util/Set;+20 java.base@16.0.1
j sun.util.locale.provider.JRELocaleProviderAdapter.lambda$getDecimalFormatSymbolsProvider$4()Ljava/text/spi/DecimalFormatSymbolsProvider;+12 java.base@16.0.1
j sun.util.locale.provider.JRELocaleProviderAdapter$$Lambda$57+0x80000005d.run()Ljava/lang/Object;+4 java.base@16.0.1
j java.security.AccessController.executePrivileged(Ljava/security/PrivilegedAction;Ljava/security/AccessControlContext;Ljava/lang/Class;)Ljava/lang/Object;+29 java.base@16.0.1
j java.security.AccessController.doPrivileged(Ljava/security/PrivilegedAction;)Ljava/lang/Object;+5 java.base@16.0.1
j sun.util.locale.provider.JRELocaleProviderAdapter.getDecimalFormatSymbolsProvider()Ljava/text/spi/DecimalFormatSymbolsProvider;+13 java.base@16.0.1
j sun.util.locale.provider.JRELocaleProviderAdapter.getLocaleServiceProvider(Ljava/lang/Class;)Ljava/util/spi/LocaleServiceProvider;+397 java.base@16.0.1
j sun.util.locale.provider.LocaleProviderAdapter.findAdapter(Ljava/lang/Class;Ljava/util/Locale;)Lsun/util/locale/provider/LocaleProviderAdapter;+42 java.base@16.0.1
j sun.util.locale.provider.LocaleProviderAdapter.getAdapter(Ljava/lang/Class;Ljava/util/Locale;)Lsun/util/locale/provider/LocaleProviderAdapter;+55 java.base@16.0.1
j java.text.DecimalFormatSymbols.getInstance(Ljava/util/Locale;)Ljava/text/DecimalFormatSymbols;+3 java.base@16.0.1
j java.text.DecimalFormat.<init>(Ljava/lang/String;)V+130 java.base@16.0.1
j FPAdder.main([Ljava/lang/String;)V+55
v ~StubRoutines::call_stub
V [libjvm.so+0xe7a774] JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, Thread*)+0x664
C 0x0023fffff6a79008
C 0x005cfffff6a7ed08
C 0x0027fffff7fa1540
C 0x0006fffff7fa4540
C 0x0021fffff7d980c8