https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81723
--- Comment #2 from Matthias Klose ---
this can be worked around with -O2.
gfortran -g -c -O3 -D_FORTIFY_SOURCE=2 -fno-range-check -fno-automatic
-fno-second-underscore -fstack-protector --param=ssp-buffer-size=4
-fno-automatic -I/home/ubuntu/libscan/cernlib-20061220+dfsg3/build/mathlib/gen
-I/home/ubuntu/libscan/cernlib-20061220+dfsg3/src/mathlib/gen
-I/home/ubuntu/libscan/cernlib-20061220+dfsg3/src/mathlib/gen/c
-I/home/ubuntu/libscan/cernlib-20061220+dfsg3/src/include -DCERNLIB_LINUX
-DCERNLIB_UNIX -DCERNLIB_LNX -DCERNLIB_QMGLIBC -DCERNLIB_QMLXIA64
-DCERNLIB_VERBOSE -DCERNLIB_DEBIAN -DDEBIAN_VERSION="20061220+dfsg3-4.3build1"
-DCERNLIB_QGETCWD -DCERNLIB_GFORTRAN -o archive/cwerf64.o
/home/ubuntu/libscan/cernlib-20061220+dfsg3/src/mathlib/gen/c/cwerf64.F
#0 0x768ec98f in __GI___libc_malloc (bytes=24) at malloc.c:2926
#1 0x011b7230 in xrealloc (oldmem=oldmem@entry=0x0,
size=size@entry=24) at ../../src/libiberty/xmalloc.c:177
#2 0x00c5bb95 in va_heap::reserve (exact=true, reserve=2,
v=@0x1f5a0a0: 0x0) at ../../src/gcc/vec.h:288
#3 vec::reserve (exact=true, nelems=2,
this=0x1f5a0a0) at ../../src/gcc/vec.h:1445
#4 vec::reserve_exact (nelems=2, this=0x1f5a0a0) at
../../src/gcc/vec.h:1465
#5 vec::create (nelems=2, this=0x1f5a0a0) at
../../src/gcc/vec.h:1480
#6 vect_create_oprnd_info (group_size=2, nops=2) at
../../src/gcc/tree-vect-slp.c:152
#7 vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0, stmts=...,
group_size=group_size@entry=2, max_nunits=max_nunits@entry=0x7fff6fb8,
loads=loads@entry=0x7fff6fc8, matches=matches@entry=0x7fffdae0,
npermutes=0x7fffdba0, tree_size=0x7fff6fb4, max_tree_size=293)
at ../../src/gcc/tree-vect-slp.c:959
#8 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff7138,
loads=loads@entry=0x7fff7148, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#9 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff72b8,
loads=loads@entry=0x7fff72c8, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#10 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff7438,
loads=loads@entry=0x7fff7448, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#11 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff75b8,
loads=loads@entry=0x7fff75c8, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#12 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff7738,
loads=loads@entry=0x7fff7748, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#13 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff78b8,
loads=loads@entry=0x7fff78c8, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#14 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff7a38,
loads=loads@entry=0x7fff7a48, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#15 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff7bb8,
loads=loads@entry=0x7fff7bc8, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#16 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff7d38,
loads=loads@entry=0x7fff7d48, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#17 0x00c5b7a1 in vect_build_slp_tree (vinfo=vinfo@entry=0x1f3dbe0,
stmts=..., group_size=group_size@entry=2,
max_nunits=max_nunits@entry=0x7fff7eb8,
loads=loads@entry=0x7fff7ec8, matches=matches@entry=0x7fffdae0,
npermutes=,
tree_size=, max_tree_size=) at
../../src/gcc/tree-vect-slp.c:1001
#18
