Disable LTO, use -march=x86-64, apply tweaks.patch.

Resolves: #1916228

compat-libgfortran-48.spec

@@ -8,6 +8,8 @@
 %undefine _annotated_build
 # Hardening slows the compiler way too much.
 %undefine _hardened_build
+# libgcc crashes left and right with LTO.
+%global _lto_cflags %%{nil}
 Summary: Compatibility Fortran runtime library version 4.8.5
 Name: compat-libgfortran-48
 %global gcc_version 4.8.5
@@ -154,6 +156,7 @@ Patch70: gcc48-pr66840.patch
 Patch71: gcc48-rh1546372.patch
 Patch72: gcc48-libc-name.patch
 Patch73: gcc48-ucontext.patch
+Patch74: gcc48-tweaks.patch
 
 Patch1301: gcc48-rh1469697-1.patch
 Patch1302: gcc48-rh1469697-2.patch
@@ -295,6 +298,7 @@ touch -r %{PATCH27} libstdc++-v3/python/libstdcxx/v6/printers.py
 %patch71 -p0 -b .rh1546372~
 %patch72 -p0 -b .libc-name~
 %patch73 -p0 -b .ucontext~
+%patch74 -p0 -b .tweaks~
 
 %patch1301 -p1 -b .stack-clash-1~
 %patch1302 -p1 -b .stack-clash-2~
@@ -356,6 +360,7 @@ OPT_FLAGS=`echo $OPT_FLAGS|sed -e 's/ -pipe / /g'`
 # GCC 4.8 doesn't know these options, but redhat-rpm-config supplies them.
 OPT_FLAGS=`echo $OPT_FLAGS|sed -e 's/ -fstack-clash-protection -fcf-protection/ /g'`
 OPT_FLAGS=`echo $OPT_FLAGS|sed -e 's/-Werror=format-security/-Wformat-security/g'`
+OPT_FLAGS=`echo $OPT_FLAGS|sed -e 's/-march=x86-64-v2/-march=x86-64/g'`
 %ifarch %{ix86}
 OPT_FLAGS=`echo $OPT_FLAGS|sed -e 's/-march=i.86//g'`
 %endif

gcc48-tweaks.patch

@@ -0,0 +1,11 @@
+--- gcc/reload.h.mp	2021-01-20 20:20:33.565766631 -0500
++++ gcc/reload.h	2021-01-20 20:20:48.437724432 -0500
+@@ -166,7 +166,7 @@ struct target_reload {
+      value indicates the level of indirect addressing supported, e.g., two
+      means that (MEM (MEM (REG n))) is also valid if (REG n) does not get
+      a hard register.  */
+-  bool x_spill_indirect_levels;
++  unsigned char x_spill_indirect_levels;
+ 
+   /* True if caller-save has been reinitialized.  */
+   bool x_caller_save_initialized_p;