https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69236
Bug ID: 69236
Summary: Wrong function call when use weak statement
Product: gcc
Version: 4.8.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: thln47 at free dot fr
Target Milestone: ---
Wrong function call when use weak statement
Hello,
Host : PC mingw32
Target : PC mingw32
I have a problem when I use weak statement with two functions.
The compiler keep the address of the first function for all of following.
So the problem occurs even I compile module1.c alone or with module2.
I try to change the optimization flags but I have the same result.
When I use another gcc version (GCC 4.9.3 for Cywin64) it's works.
Thanks for reply.
------------------------------------------------------------------------------------
Here is output :
------------------------------------------------------------------------------------
WEAK BUG Checker Compiler version : 4.8.1!
function_Get_F1 = 004016B0
function_Get_F2 = 004016B0
..\src\module1.c : Get_F1
..\src\module1.c : Get_F1
BUG (test=1)
------------------------------------------------------------------------------------
Here is my code for module1.c
------------------------------------------------------------------------------------
/*
* module1.c
*
* Created on: Jan 11, 2016
* Author: Thierry
*/
#include <stdio.h>
#include <stdint.h>
//#define __WEAK
#define __WEAK __attribute__((weak))
extern uint16_t Get_F1(void);
extern uint16_t Get_F2(uint16_t param_index);
__WEAK uint16_t Get_F1(void) {
printf("%s : %s\n", __FILE__, __FUNCTION__);
return 1;
}
__WEAK uint16_t Get_F2(uint16_t param_index) {
printf("%s : %s\n", __FILE__, __FUNCTION__);
return 1+param_index;
}
void bug_highlight(void) {
uint16_t (* function_Get_F1)(void);
uint16_t (* function_Get_F2)(uint16_t param_index);
function_Get_F1 = &Get_F1;
function_Get_F2 = &Get_F2;
printf("function_Get_F1 = %p\n", function_Get_F1);
printf("function_Get_F2 = %p\n", function_Get_F2);
uint16_t test;
test = Get_F1();
test = Get_F2(test);
if (test==2) {
printf("test Ok with module1\n");
} else if (test==20) {
printf("test Ok with module2\n");
} else {
printf("BUG (test=%d)\n", test);
}
}
int main(void){
setbuf(stdout, NULL);
printf("WEAK BUG Checker Compiler version : %s!\n", __VERSION__);
bug_highlight();
return 0;
}
------------------------------------------------------------------------------------
Here is my code for module2.c
------------------------------------------------------------------------------------
/*
* module2.c
*
* Created on: Jan 11, 2016
* Author: Thierry
*/
#include <stdio.h>
#include <stdint.h>
uint16_t Get_F1(void) {
printf("%s : %s\n", __FILE__, __FUNCTION__);
return 10;
}
uint16_t Get_F2(uint16_t param_index) {
printf("%s : %s\n", __FILE__, __FUNCTION__);
return 10+param_index;
}
------------------------------------------------------------------------------------
Here is compiler command line
------------------------------------------------------------------------------------
gcc -O0 -g3 -Wall -c -fmessage-length=0 -Wextra -v -o src\module1.o
..\src\module1.c
Using built-in specs.
COLLECT_GCC=D:\Atollic\TrueSTUDIO for ARM 5.4.0\PCTools\bin\gcc.exe
Target: mingw32
Configured with: ../gcc-4.8.1/configure --prefix=/mingw --host=mingw32
--build=mingw32 --without-pic --enable-shared --enable-static --with-gnu-ld
--enable-lto --enable-libssp --disable-multilib
--enable-languages=c,c++,fortran,objc,obj-c++,ada --disable-sjlj-exceptions
--with-dwarf2 --disable-win32-registry --enable-libstdcxx-debug
--enable-version-specific-runtime-libs
--with-gmp=/usr/src/pkg/gmp-5.1.2-1-mingw32-src/bld
--with-mpc=/usr/src/pkg/mpc-1.0.1-1-mingw32-src/bld --with-mpfr=
--with-system-zlib --with-gnu-as --enable-decimal-float=yes --enable-libgomp
--enable-threads --with-libiconv-prefix=/mingw32 --with-libintl-prefix=/mingw
--disable-bootstrap LDFLAGS=-s CFLAGS=-D_USE_32BIT_TIME_T
Thread model: win32
gcc version 4.8.1 (GCC)
COLLECT_GCC_OPTIONS='-O0' '-g3' '-Wall' '-c' '-fmessage-length=0' '-Wextra'
'-v' '-o' 'src\module1.o' '-mtune=generic' '-march=pentiumpro'
d:/atollic/truestudio for arm
5.4.0/pctools/bin/../libexec/gcc/mingw32/4.8.1/cc1.exe -quiet -v -iprefix
d:\atollic\truestudio for arm 5.4.0\pctools\bin\../lib/gcc/mingw32/4.8.1/ -dD
..\src\module1.c -quiet -dumpbase module1.c -mtune=generic -march=pentiumpro
-auxbase-strip src\module1.o -g3 -O0 -Wall -Wextra -version -fmessage-length=0
-o C:\Users\Thierry\AppData\Local\Temp\cc1BmIoz.s
GNU C (GCC) version 4.8.1 (mingw32)
compiled by GNU C version 4.8.1, GMP version 5.1.2, MPFR version 3.1.2,
MPC version 1.0.1
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring duplicate directory "d:/atollic/truestudio for arm
5.4.0/pctools/lib/gcc/../../lib/gcc/mingw32/4.8.1/include"
ignoring duplicate directory "d:/atollic/truestudio for arm
5.4.0/pctools/lib/gcc/../../lib/gcc/mingw32/4.8.1/../../../../include"
ignoring nonexistent directory "/mingw/include"
ignoring duplicate directory "d:/atollic/truestudio for arm
5.4.0/pctools/lib/gcc/../../lib/gcc/mingw32/4.8.1/include-fixed"
ignoring duplicate directory "d:/atollic/truestudio for arm
5.4.0/pctools/lib/gcc/../../lib/gcc/mingw32/4.8.1/../../../../mingw32/include"
ignoring nonexistent directory "/mingw/include"
#include "..." search starts here:
#include <...> search starts here:
d:\atollic\truestudio for arm
5.4.0\pctools\bin\../lib/gcc/mingw32/4.8.1/include
d:\atollic\truestudio for arm
5.4.0\pctools\bin\../lib/gcc/mingw32/4.8.1/../../../../include
d:\atollic\truestudio for arm
5.4.0\pctools\bin\../lib/gcc/mingw32/4.8.1/include-fixed
d:\atollic\truestudio for arm
5.4.0\pctools\bin\../lib/gcc/mingw32/4.8.1/../../../../mingw32/include
End of search list.
GNU C (GCC) version 4.8.1 (mingw32)
compiled by GNU C version 4.8.1, GMP version 5.1.2, MPFR version 3.1.2,
MPC version 1.0.1
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 767202a405449496e68a54c4eee91a28
COLLECT_GCC_OPTIONS='-O0' '-g3' '-Wall' '-c' '-fmessage-length=0' '-Wextra'
'-v' '-o' 'src\module1.o' '-mtune=generic' '-march=pentiumpro'
d:/atollic/truestudio for arm
5.4.0/pctools/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/as.exe -v -o
src\module1.o C:\Users\Thierry\AppData\Local\Temp\cc1BmIoz.s
GNU assembler version 2.23.2 (mingw32) using BFD version (GNU Binutils) 2.23.2
COMPILER_PATH=d:/atollic/truestudio for arm
5.4.0/pctools/bin/../libexec/gcc/mingw32/4.8.1/;d:/atollic/truestudio for arm
5.4.0/pctools/bin/../libexec/gcc/;d:/atollic/truestudio for arm
5.4.0/pctools/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/
LIBRARY_PATH=d:/atollic/truestudio for arm
5.4.0/pctools/bin/../lib/gcc/mingw32/4.8.1/;d:/atollic/truestudio for arm
5.4.0/pctools/bin/../lib/gcc/;d:/atollic/truestudio for arm
5.4.0/pctools/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/lib/;d:/atollic/truestudio
for arm 5.4.0/pctools/bin/../lib/gcc/mingw32/4.8.1/../../../
COLLECT_GCC_OPTIONS='-O0' '-g3' '-Wall' '-c' '-fmessage-length=0' '-Wextra'
'-v' '-o' 'src\module1.o' '-mtune=generic' '-march=pentiumpro'
gcc -o weak_bug.exe src\module1.o
------------------------------------------------------------------------------------
Here is disassemby of bug_highlight function
------------------------------------------------------------------------------------
29 void bug_highlight(void) {
bug_highlight:
0040170b: push %ebp
0040170c: mov %esp,%ebp
0040170e: sub $0x28,%esp
34 function_Get_F1 = &Get_F1;
00401711: movl $0x4016b0,-0xc(%ebp)
35 function_Get_F2 = &Get_F2;
00401718: movl $0x4016b0,-0x10(%ebp)
37 printf("function_Get_F1 = %p\n", function_Get_F1);
0040171f: mov -0xc(%ebp),%eax
00401722: mov %eax,0x4(%esp)
00401726: movl $0x40507e,(%esp)
0040172d: call 0x403778 <printf>
38 printf("function_Get_F2 = %p\n", function_Get_F2);
00401732: mov -0x10(%ebp),%eax
00401735: mov %eax,0x4(%esp)
00401739: movl $0x405094,(%esp)
00401740: call 0x403778 <printf>
42 test = Get_F1();
00401745: call 0x4016b0 <Get_F1>
0040174a: mov %ax,-0x12(%ebp)
43 test = Get_F2(test);
0040174e: movzwl -0x12(%ebp),%eax
00401752: mov %eax,(%esp)
00401755: call 0x4016b0 <Get_F1>
0040175a: mov %ax,-0x12(%ebp)
45 if (test==2) {
0040175e: cmpw $0x2,-0x12(%ebp)
00401763: jne 0x401773 <bug_highlight+104>
46 printf("test Ok with module1\n");
00401765: movl $0x4050aa,(%esp)
0040176c: call 0x403780 <puts>
00401771: jmp 0x40179c <bug_highlight+145>
47 } else if (test==20) {
00401773: cmpw $0x14,-0x12(%ebp)
00401778: jne 0x401788 <bug_highlight+125>
48 printf("test Ok with module2\n");
0040177a: movl $0x4050bf,(%esp)
00401781: call 0x403780 <puts>
00401786: jmp 0x40179c <bug_highlight+145>
50 printf("BUG (test=%d)\n", test);
00401788: movzwl -0x12(%ebp),%eax
0040178c: mov %eax,0x4(%esp)
00401790: movl $0x4050d4,(%esp)
00401797: call 0x403778 <printf>
52 }
0040179c: leave
0040179d: ret
