I built an x86_64-w64-mingw32 cross compiler under x86_64 linux using
latest gcc SVN code, then use this cross compiler to build ffmpeg.
the program runs failed, it seem that epilogue code in aac_encode_frame()
adjust wrong rsp register.
at function aac_encode_frame() begin :
0x69fb91 <aac_encode_frame+0>: push %rbp
0x69fb91 <aac_encode_frame+1>: mov %rsp,%rbp
0x69fb94 <aac_encode_frame+4>: push %r15
0x69fb96 <aac_encode_frame+6>: push %r14
0x69fb98 <aac_encode_frame+8>: push %r13
0x69fb9a <aac_encode_frame+10>: push %r12
0x69fb9c <aac_encode_frame+12>: push %rdi
0x69fb9d <aac_encode_frame+13>: push %rsi
0x69fb9e <aac_encode_frame+14>: push %rbx
0x69fb9f <aac_encode_frame+15>: sub $0x178,%rsp
0x69fba6 <aac_encode_frame+22>: mov %rdx,0x18(%rbp)
0x69fbaa <aac_encode_frame+26>: mov %rcx,0x10(%rbp)
it push 7 registers, when it about to quit :
0x69fd65 <aac_encode_frame+469>: lea -0x60(%rbp),%rsp
0x69fd69 <aac_encode_frame+473>: movdqa 0x150(%rsp),%xmm6
0x69fd72 <aac_encode_frame+482>: movdqa 0x160(%rsp),%xmm7
0x69fd7b <aac_encode_frame+491>: add $0x20,%rsp
0x69fd7f <aac_encode_frame+495>: pop %rbx
0x69fd80 <aac_encode_frame+496>: pop %rsi
0x69fd81 <aac_encode_frame+497>: pop %rdi
0x69fd82 <aac_encode_frame+498>: pop %r12
0x69fd84 <aac_encode_frame+500>: pop %r13
0x69fd86 <aac_encode_frame+502>: pop %r14
0x69fd88 <aac_encode_frame+504>: pop %r15
0x69fd8a <aac_encode_frame+506>: leaveq
0x69fd8b <aac_encode_frame+507>: retq
it should "add 0x28 %rsp ( not 0x20 )" after "lea -0x60(%rbp),%rsp"
the compile command is :
/compile/mingw-w64-dgn/cross/bin/x86_64-w64-mingw32-gcc -DHAVE_AV_CONFIG_H -I.
-I"/compile/mingw-w64-dgn/lib_source/ffmpeg" -D_ISOC99_SOURCE
-D_POSIX_C_SOURCE=200112 -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -std=c99
-fno-common -fomit-frame-pointer -g -Wdeclaration-after-statement -Wall
-Wno-switch -Wdisabled-optimization -Wpointer-arith -Wredundant-decls
-Wno-pointer-sign -Wcast-qual -Wwrite-strings -Wtype-limits -Wundef -O3
-fno-strict-aliasing -fno-math-errno -fno-signed-zeros -fno-tree-vectorize
-MMD -MF libavcodec/aacenc.d -MT libavcodec/aacenc.o -c -o a.o -save-temps
/compile/mingw-w64-dgn/lib_source/ffmpeg/libavcodec/aacenc.c
the -save-temps output is attached.
-O1 -O2 -O3 all has this problem, -O0 has no problem.
--
Summary: wrong optimise code, epilogue code adjust wrong rsp
before pop
Product: gcc
Version: 4.5.0
Status: UNCONFIRMED
Severity: major
Priority: P3
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: drangon dot mail at gmail dot com
GCC build triplet: x86_64-gnu-linux
GCC host triplet: x86_64-gnu-linux
GCC target triplet: x86_64-w64-mingw32
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41184
