[Bug ipa/96291] [10/11 Regression] -flto fails as "internal compiler error: Segmentation fault" during IPA pass: cp incall_for_symbol_thunks_and_aliases()

[slyfox at inbox dot ru]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96291

--- Comment #5 from Sergei Trofimovich <slyfox at inbox dot ru> ---
I shrunk example to "single-file" (almost) example to ease local tweaking:

$ cat 1file.c
  void e(void);
  void f(void);
  void a(int, int);
  void c(int);
  #ifdef COMPILE_F1
  int b;
  void c(int d) {
    f();
    a(b, 0);
  }
  void e(void) { c(0); }
  #endif
  #ifdef COMPILE_F2
  void f(void) { c(0); }
  #endif
  #ifdef COMPILE_F3
  void a(int a1, int a2) { e(); }
  #endif

$ x86_64-pc-linux-gnu-gcc -c -O2 -flto -o f1.o 1file.c -DCOMPILE_F1
$ x86_64-pc-linux-gnu-gcc -c -O2 -flto -o f2.o 1file.c -DCOMPILE_F2
$ x86_64-pc-linux-gnu-gcc -c -O2 -flto -O0 -o f3.o 1file.c -DCOMPILE_F3
$ x86_64-pc-linux-gnu-gcc -O2 -flto -o sdb f1.o f2.o f3.o
during IPA pass: cp
lto1: internal compiler error: Segmentation fault