I have a simple testcase:
void test()
{
}
# arm-linux-gcc test.c -S -O2 produces:
test:
@ args = 0, pretend = 0, frame = 0
@ frame_needed = 0, uses_anonymous_args = 0
@ link register save eliminated.
@ lr needed for prologue
mov pc, lr
# arm-linux-gcc test.c -S -O2 -mcpu=arm7tdmi-s produces:
test:
@ args = 0, pretend = 0, frame = 0
@ frame_needed = 0, uses_anonymous_args = 0
@ link register save eliminated.
@ lr needed for prologue
bx lr
-mthumb-interwork is disabled by default (vide man).
why gcc4 produces "bx lr" ? (gcc34 works fine).
# arm-linux-gcc -v
Reading specs from /usr/lib/gcc/arm-linux/4.0.0/specs
Configured with: ../configure --prefix=/usr
--with-sysroot=/home/users/pluto/rpm/BUILD/gcc-4.0-20050130/fake-root
--infodir=/usr/share/info --mandir=/usr/share/man --bindir=/usr/bin
--libdir=/usr/lib --libexecdir=/usr/lib --disable-shared --disable-threads
--enable-languages=c,c++ --enable-c99 --enable-long-long --with-gnu-as
--with-gnu-ld --with-system-zlib --with-multilib
--with-sysroot=/home/users/pluto/rpm/BUILD/gcc-4.0-20050130/fake-root
--without-x --target=arm-linux --host=i686-pld-linux --build=i686-pld-linux
Thread model: single
gcc version 4.0.0 20050130 (experimental)
--
Summary: unexpected "bx lr" in arm mode.
Product: gcc
Version: 4.0.0
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: regression
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: pluto at pld-linux dot org
CC: gcc-bugs at gcc dot gnu dot org
GCC build triplet: i686-linux
GCC host triplet: i686-linux
GCC target triplet: arm-linux
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19935
