- x86_64 looks OK
- seems LTO related, removing the LTO flags makes it compile

reproduced with
/usr/libexec/gcc/ppc64le-redhat-linux/12/cc1plus -O2 -fexceptions -g -grecord-gcc-switches -Wall -Werror=format-security -fstack-protector-strong -m64 -mcpu=power8 -mtune=power8 -fasynchronous-unwind-tables -fstack-clash-protection -Winvalid-pch -fexceptions -fPIC -flto=auto -ffat-lto-objects < ExpressionPreprocessed.ii

and minimal reproducer is
/usr/libexec/gcc/ppc64le-redhat-linux/12/cc1plus -flto=auto -ffat-lto-objects < ExpressionPreprocessed.ii

Created attachment 1852575 [details]
preprocessed source 2

probably same issue in another project

reproduced by
/usr/libexec/gcc/ppc64le-redhat-linux/12/cc1plus -O2 -flto=auto -ffat-lto-objects < PagePrinter.ii

here either removing -O2 or the LTO options make it pass


the complete error message
<mock-chroot> sh-5.1# g++ -c -pedantic -Wno-long-long -std=c++11 -O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -m64 -mcpu=power8 -mtune=power8 -fasynchronous-unwind-tables -fstack-clash-protection -Wall -Wextra -D_REENTRANT -fPIC -DQT_NO_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -I. -IHercStudio -IHercConfiguration -IHercUtilities -IHercPrinter -I/usr/include/qt5 -I/usr/include/qt5/QtWidgets -I/usr/include/qt5/QtGui -I/usr/include/qt5/QtNetwork -I/usr/include/qt5/QtCore -Imoc -Iui -I/usr/lib64/qt5/mkspecs/linux-g++ -o obj/PagePrinter.o HercPrinter/PagePrinter.cpp
HercPrinter/PagePrinter.cpp: In member function ‘virtual void PdfPrinter::setValues(bool)’:
HercPrinter/PagePrinter.cpp:85:24: warning: ‘virtual void QPdfWriter::setPageSizeMM(const QSizeF&)’ is deprecated: Use setPageSize(QPageSize(size, QPageSize::Millimeter)) instead [-Wdeprecated-declarations]
   85 |     mPdf->setPageSizeMM(QSize(mPaperWidth*25.4L, mPaperHeight*25.4L));
      |     ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/qt5/QtGui/QPdfWriter:1,
                 from HercPrinter/PagePrinter.h:33,
                 from HercPrinter/PagePrinter.cpp:1:
/usr/include/qt5/QtGui/qpdfwriter.h:98:10: note: declared here
   98 |     void setPageSizeMM(const QSizeF &size) override;
      |          ^~~~~~~~~~~~~
during RTL pass: final
HercPrinter/PagePrinter.cpp: In member function ‘PagePrinter::PagePrinter(QSharedPointer<Stationery>&, QPainter&)’:
HercPrinter/PagePrinter.cpp:15:1: internal compiler error: Segmentation fault
   15 | PagePrinter::PagePrinter(StationeryPtr &stationery, QPainter &painter) :
      | ^~~~~~~~~~~
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://bugzilla.redhat.com/bugzilla> for instructions.
The bug is not reproducible, so it is likely a hardware or OS problem.

Reproduced, same backtrace as in bug 2043357:

during RTL pass: final
HercPrinter/PagePrinter.cpp: In member function ‘PagePrinter::PagePrinter(QSharedPointer<Stationery>&, QPainter&)’:
HercPrinter/PagePrinter.cpp:15:1: internal compiler error: tree check: expected class ‘type’, have ‘declaration’ (translation_unit_decl) in base_ctor_omit_inherited_parms, at cp/method.cc:568
0x1024ace3 tree_class_check_failed(tree_node const*, tree_code_class, char const*, int, char const*)
	/home/polacek/src/gcc/gcc/tree.cc:8755
0x10484f03 tree_class_check
	/home/polacek/src/gcc/gcc/tree.h:3564
0x10484f03 base_ctor_omit_inherited_parms(tree_node*)
	/home/polacek/src/gcc/gcc/cp/method.cc:568
0x1046f7b3 write_method_parms
	/home/polacek/src/gcc/gcc/cp/mangle.cc:2798
0x1046fbf3 write_bare_function_type
	/home/polacek/src/gcc/gcc/cp/mangle.cc:2760
0x1046fd1b write_encoding
	/home/polacek/src/gcc/gcc/cp/mangle.cc:834
0x104722f3 mangle_decl_string
	/home/polacek/src/gcc/gcc/cp/mangle.cc:4034
0x1047251f get_mangled_id
	/home/polacek/src/gcc/gcc/cp/mangle.cc:4055
0x104728ff mangle_decl(tree_node*)
	/home/polacek/src/gcc/gcc/cp/mangle.cc:4093
0x113f92f3 rs6000_globalize_decl_name
	/home/polacek/src/gcc/gcc/config/rs6000/rs6000.cc:28218
0x113b7c93 globalize_decl
	/home/polacek/src/gcc/gcc/varasm.cc:6146
0x113befff assemble_start_function(tree_node*, char const*)
	/home/polacek/src/gcc/gcc/varasm.cc:1965
0x10a0670f rest_of_handle_final
	/home/polacek/src/gcc/gcc/final.cc:4281
0x10a0670f execute
	/home/polacek/src/gcc/gcc/final.cc:4363

Reduced testcase:
// { dg-do compile { target { powerpc*-*-* && lp64 && le } } }
// { dg-options "-O2 -flto=auto -ffat-lto-objects -mabi=ieeelongdouble" }

struct A { A(int); };
struct B { float b; };
struct C : B { C(); };
C::C() { A(b * 25.4L); }

The bug is in:
/* Create an alias for a mangled name where we have changed the mangling (in
   GCC 8.1, we used U10__float128, and now we use u9__ieee128).  This is called
   via the target hook TARGET_ASM_GLOBALIZE_DECL_NAME.  */

#if TARGET_ELF && RS6000_WEAK
static void
rs6000_globalize_decl_name (FILE * stream, tree decl)
{
  const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);

  targetm.asm_out.globalize_label (stream, name);
  
  if (rs6000_passes_ieee128 && name[0] == '_' && name[1] == 'Z')
    {
      tree save_asm_name = DECL_ASSEMBLER_NAME (decl);
      const char *old_name;

      ieee128_mangling_gcc_8_1 = true;
      lang_hooks.set_decl_assembler_name (decl);
      old_name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
      SET_DECL_ASSEMBLER_NAME (decl, save_asm_name);
      ieee128_mangling_gcc_8_1 = false;

      if (strcmp (name, old_name) != 0)
        {
          fprintf (stream, "\t.weak %s\n", old_name);
          fprintf (stream, "\t.set %s,%s\n", old_name, name);
        }
    }
}
#endif

This is just wrong, mangling is only possible before free_lang_data, not after that, everything should be mangled by then.
So, IMHO the backend should note that during mangling that it emitted some u9__ieee128 (when rs6000_mangle_type returns it)
and through some hook should cooperate with the C++ FE to create a mangling alias like the FE creates mangling aliases for -fabi-version*.

https://koji.fedoraproject.org/scratch/jakub/task_81787698/ is a scratch build of gcc that could fix this.

tested with hercstudio (the 2nd case here) and it builds OK, no segfaults

Please retry against gcc-12.0.1-0.3.fc36 and annobin-10.51-2.fc36 now in rawhide.

the original issue went away, but there is a new one

...
libtool: link: g++  -fPIC -DPIC -shared -nostdlib /usr/lib/gcc/ppc64le-redhat-linux/12/../../../../lib64/crti.o /usr/lib/gcc/ppc64le-redhat-linux/12/crtbeginS.o  .libs/CharacterView.o .libs/DigitView.o .libs/ExpressionExecutor.o .libs/ExpressionParser.o .libs/ExpressionPreprocessed.o .libs/ExpressionTestCases.o .libs/ExpressionTester.o .libs/FileContentBase.o .libs/FileContentBuffered.o .libs/FileContentDisk.o .libs/HexEditLineBuffer.o .libs/HexEditor.o .libs/HexEditPanel.o .libs/HexEditViewBase.o .libs/SearchDialog.o .libs/SelectStoredExpressionDlg.o .libs/TestCasesDlg.o   ../../../sdk/.libs/libcodeblocks.so -lgdk-3 -lz -lpangocairo-1.0 -lpango-1.0 -lharfbuzz -lgdk_pixbuf-2.0 -lcairo-gobject -lcairo -lgobject-2.0 -lglib-2.0 -ltinyxml -lsquirrel -lsqstdlib -lwx_gtk3u_aui-3.0 -lwx_gtk3u_propgrid-3.0 -lwx_gtk3u_richtext-3.0 -lwx_gtk3u_xrc-3.0 -lwx_gtk3u_webview-3.0 -lwx_gtk3u_html-3.0 -lwx_gtk3u_qa-3.0 -lwx_gtk3u_adv-3.0 -lwx_gtk3u_core-3.0 -lwx_baseu_xml-3.0 -lwx_baseu_net-3.0 -lwx_baseu-3.0 -lpthread -ldl -L/usr/lib/gcc/ppc64le-redhat-linux/12 -L/usr/lib/gcc/ppc64le-redhat-linux/12/../../../../lib64 -L/lib/../lib64 -L/usr/lib/../lib64 -L/usr/lib/gcc/ppc64le-redhat-linux/12/../../.. -lstdc++ -lm -lc -lgcc_s /usr/lib/gcc/ppc64le-redhat-linux/12/crtendS.o /usr/lib/gcc/ppc64le-redhat-linux/12/../../../../lib64/crtn.o -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -O2 -flto=auto -g -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mcpu=power8 -mtune=power8 -Wl,--no-undefined -Wl,-z -Wl,relro -Wl,--as-needed -Wl,-z -Wl,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -Wl,--build-id=sha1 -Wl,-dT -Wl,/builddir/build/BUILD/codeblocks-20.03/.package_note-codeblocks-20.03-11.fc36.ppc64le.ld -pthread   -pthread -Wl,-soname -Wl,libHexEditor.so -o .libs/libHexEditor.so
/usr/bin/ld: /usr/lib/gcc/ppc64le-redhat-linux/12/libgcc.a(float128-ifunc.o):(.data+0x0): undefined reference to `__parse_hwcap_and_convert_at_platform'
collect2: error: ld returned 1 exit status
make[4]: *** [Makefile:617: libHexEditor.la] Error 1
make[4]: Leaving directory '/builddir/build/BUILD/codeblocks-20.03/src/plugins/contrib/HexEditor'

This is from a fresh build - https://koji.fedoraproject.org/koji/taskinfo?taskID=82004527

You shouldn't use -nostdlib. If you do that, you are on your own. The issue here is -l flag (-lgcc_s after -lc) ordering and -Wl,--as-needed.

I think it's libtool in "module" mode ...

/bin/sh ../../../../libtool  --tag=CXX   --mode=link g++  -O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -m64 -mcpu=power8 -mtune=power8 -fasynchronous-unwind-tables -fstack-clash-protection -Winvalid-pch -fPIC -fexceptions -module -shared -version-info 0:1:0 -no-undefined -avoid-version -Wl,--no-undefined -Wl,-z,relro -Wl,--as-needed  -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -Wl,--build-id=sha1 -Wl,-dT,/builddir/build/BUILD/codeblocks-20.03/.package_note-codeblocks-20.03-11.fc36.ppc64le.ld -o libHexEditor.la -rpath /usr/lib64/codeblocks/plugins CharacterView.lo DigitView.lo ExpressionExecutor.lo ExpressionParser.lo ExpressionPreprocessed.lo ExpressionTestCases.lo ExpressionTester.lo FileContentBase.lo FileContentBuffered.lo FileContentDisk.lo HexEditLineBuffer.lo HexEditor.lo HexEditPanel.lo HexEditViewBase.lo SearchDialog.lo SelectStoredExpressionDlg.lo TestCasesDlg.lo ../../../sdk/libcodeblocks.la -pthread   -lwx_gtk3u_aui-3.0 -lwx_gtk3u_propgrid-3.0 -lwx_gtk3u_richtext-3.0 -lwx_gtk3u_xrc-3.0 -lwx_gtk3u_webview-3.0 -lwx_gtk3u_html-3.0 -lwx_gtk3u_qa-3.0 -lwx_gtk3u_adv-3.0 -lwx_gtk3u_core-3.0 -lwx_baseu_xml-3.0 -lwx_baseu_net-3.0 -lwx_baseu-3.0  -lpthread -ldl

hmm, libtool itself contains
...
postdeps="-lstdc++ -lm -lgcc_s -lc -lgcc_s"
...

which should be the right set, but somehow the build lacks the first -lgcc_s ...

IMO this is a libtool bug, it shouldn't be de-duplicating the libs in $postdeps. When I pass --preserve-dup-deps the linker command contains the right sequence of -lgcc_s and -lc

or this change in libtool

--- libtool.orig	2022-01-27 18:02:50.421704711 +0000
+++ libtool	2022-01-27 18:02:56.221776202 +0000
@@ -2930,7 +2930,7 @@
     case $host in
       # Solaris2 added to fix http://debbugs.gnu.org/cgi/bugreport.cgi?bug=16452
       # see also: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59788
-      *cygwin* | *mingw* | *pw32* | *cegcc* | *solaris2* | *os2* | *linux*)
+      *cygwin* | *mingw* | *pw32* | *cegcc* | *solaris2* | *os2*)
         # don't eliminate duplications in $postdeps and $predeps
         opt_duplicate_compiler_generated_deps=:
         ;;

This bug appears to have been reported against 'rawhide' during the Fedora 36 development cycle.
Changing version to 36.

> -      *cygwin* | *mingw* | *pw32* | *cegcc* | *solaris2* | *os2* | *linux*)
> +      *cygwin* | *mingw* | *pw32* | *cegcc* | *solaris2* | *os2*)

I don't have time for full review of this (I've just quickly seen the
downstream commit 2103f3557ecaa87d60ddb9c8d2f490c8ead9f3a0).  I just have a
warning that his might be tricky.

Any such downstream change in Libtool needs to be done very carefully
because patching ltmain.in in Rawhide not only affects the Rawhide builds —
it will also affect the variety of upstream `make dist` release tarballs.
Therefore, while the patch might work on Fedora 37+, it may get distributed
to the world and fail the build on other distributions (no big immediate risk,
but long term upstream maintainers might prefer doing the development on other
distros, just to assure they provide clean `make dist` tarballs).

This message is a reminder that Fedora Linux 36 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 36 on 2023-05-16.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
'version' of '36'.

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