https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84615
--- Comment #5 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
The following test (reduced from gfortran.dg/pr46588.f90)
function aufun(pm)
character(len = *) pm
character(len = *) aufun
print *, ">", pm, "<"
aufun = 'Oh' // trim(pm)
end function aufun
program ds
implicit none
character(len = 4) :: ins = ' no!'
character(len = 20) st, aufun
logical(4) :: tst
print *, ">", ins, "<"
st = aufun(ins)
print *, ">", st, "<"
end
gives
> no!<
Program received signal SIGSEGV: Segmentation fault - invalid memory reference.
at run time when compiled with -m32 -fdefault-integer-8.
I don't see any difference when comparing the outputs of -fdump-tree-original
with -m32 or -m32 -fdefault-integer-8, but I see the following difference in
the assembly files
--- pr46588_db.s 2018-03-05 12:50:58.000000000 +0100
+++ pr46588_db_m32.s 2018-03-05 12:50:41.000000000 +0100
@@ -3,8 +3,7 @@
# GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
# options passed: pr46588_db.f90 -fPIC -m32 -mmacosx-version-min=10.13.0
-# -mtune=corei7 -march=corei7 -fdefault-integer-8 -fdump-tree-original
-# -fverbose-asm
+# -mtune=corei7 -march=corei7 -fdump-tree-original -fverbose-asm
# -fintrinsic-modules-path
/opt/gcc/gcc8w/lib/gcc/x86_64-apple-darwin17.4.0/8.0.1/i386/finclude
# options enabled: -Wnonportable-cfstrings -fPIC
# -faggressive-loop-optimizations -fasynchronous-unwind-tables
@@ -255,16 +254,14 @@ L2$pb:
call __gfortran_st_write_done #
addl $16, %esp #,
# pr46588_db.f90:14: st = aufun(ins)
- subl $12, %esp #,
pushl $4 #
leal _ins.3702-L2$pb(%ebx), %eax #, tmp97
pushl %eax # tmp97
- pushl $0 #
pushl $20 #
leal -48(%ebp), %eax #, tmp98
pushl %eax # tmp98
call _aufun_ #
- addl $32, %esp #,
+ addl $16, %esp #,
movl -48(%ebp), %eax # MEM[(c_char * {ref-all})&str.5], tmp99
movl %eax, -28(%ebp) # tmp99, MEM[(c_char * {ref-all})&st]
movl -44(%ebp), %eax # MEM[(c_char * {ref-all})&str.5], tmp100
