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Aug 11, 2023 . 2 changed files with 11 additions and 10 deletions.There are no files selected for viewing
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -2,11 +2,11 @@ extern unsigned long _GLOBAL_OFFSET_TABLE_ []; extern unsigned long SOME_GLOBAL; int main() { auto foo1 = &_GLOBAL_OFFSET_TABLE_; auto foo2 = _GLOBAL_OFFSET_TABLE_; auto bar1 = &SOME_GLOBAL; auto bar2 = SOME_GLOBAL; return 0; } This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -21,22 +21,23 @@ extern unsigned long SOME_GLOBAL; int main() { 1000: 55 push rbp 1001: 48 89 e5 mov rbp,rsp auto foo1 = &_GLOBAL_OFFSET_TABLE_; 1004: 48 8d 05 dd 2f 00 00 lea rax,[rip+0x2fdd] # 3fe8 <_GLOBAL_OFFSET_TABLE_> 100b: 48 89 45 f8 mov QWORD PTR [rbp-0x8],rax auto foo2 = _GLOBAL_OFFSET_TABLE_; 100f: 48 8d 05 d2 2f 00 00 lea rax,[rip+0x2fd2] # 3fe8 <_GLOBAL_OFFSET_TABLE_> 1016: 48 89 45 f0 mov QWORD PTR [rbp-0x10],rax auto bar1 = &SOME_GLOBAL; 101a: 48 8d 05 df 2f 00 00 lea rax,[rip+0x2fdf] # 4000 <SOME_GLOBAL> 1021: 48 89 45 e8 mov QWORD PTR [rbp-0x18],rax auto bar2 = SOME_GLOBAL; 1025: 48 8b 05 d4 2f 00 00 mov rax,QWORD PTR [rip+0x2fd4] # 4000 <SOME_GLOBAL> 102c: 48 89 45 e0 mov QWORD PTR [rbp-0x20],rax return 0; 1030: b8 00 00 00 00 mov eax,0x0 } 1035: 5d pop rbp 1036: c3 ret @@ -65,17 +66,17 @@ int main() { 1290: 55 push rbp 1291: 48 89 e5 mov rbp,rsp 1294: c7 45 fc 00 00 00 00 mov DWORD PTR [rbp-0x4],0x0 auto foo1 = &_GLOBAL_OFFSET_TABLE_; 129b: 48 8b 05 c6 20 00 00 mov rax,QWORD PTR [rip+0x20c6] # 3368 <_GLOBAL_OFFSET_TABLE_> 12a2: 48 89 45 f0 mov QWORD PTR [rbp-0x10],rax auto foo2 = _GLOBAL_OFFSET_TABLE_; 12a6: 48 8b 05 bb 20 00 00 mov rax,QWORD PTR [rip+0x20bb] # 3368 <_GLOBAL_OFFSET_TABLE_> 12ad: 48 89 45 e8 mov QWORD PTR [rbp-0x18],rax auto bar1 = &SOME_GLOBAL; 12b1: 48 8d 05 a8 20 00 00 lea rax,[rip+0x20a8] # 3360 <SOME_GLOBAL> 12b8: 48 89 45 e0 mov QWORD PTR [rbp-0x20],rax auto bar2 = SOME_GLOBAL; 12bc: 48 8d 05 9d 20 00 00 lea rax,[rip+0x209d] # 3360 <SOME_GLOBAL> 12c3: 48 8b 00 mov rax,QWORD PTR [rax] 12c6: 48 89 45 d8 mov QWORD PTR [rbp-0x28],rax -
Aug 11, 2023 . 1 changed file with 88 additions and 0 deletions.There are no files selected for viewing
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,88 @@ g++ -c -g -fpie -o foo.o foo.cpp g++ -c -g -fpie -o bar.o bar.cpp ld -pie -o got foo.o bar.o g++ --version g++ (Debian 12.3.0-5) 12.3.0 Copyright (C) 2022 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. objdump -M intel -DS -j .text got got: file format elf64-x86-64 Disassembly of section .text: 0000000000001000 <main>: extern unsigned long _GLOBAL_OFFSET_TABLE_ []; extern unsigned long SOME_GLOBAL; int main() { 1000: 55 push rbp 1001: 48 89 e5 mov rbp,rsp auto foo1 = reinterpret_cast<unsigned long*>(&_GLOBAL_OFFSET_TABLE_); 1004: 48 8d 05 dd 2f 00 00 lea rax,[rip+0x2fdd] # 3fe8 <_GLOBAL_OFFSET_TABLE_> 100b: 48 89 45 f8 mov QWORD PTR [rbp-0x8],rax auto foo2 = reinterpret_cast<unsigned long*>( _GLOBAL_OFFSET_TABLE_); 100f: 48 8d 05 d2 2f 00 00 lea rax,[rip+0x2fd2] # 3fe8 <_GLOBAL_OFFSET_TABLE_> 1016: 48 89 45 f0 mov QWORD PTR [rbp-0x10],rax auto bar1 = &SOME_GLOBAL; 101a: 48 8d 05 df 2f 00 00 lea rax,[rip+0x2fdf] # 4000 <SOME_GLOBAL> 1021: 48 89 45 e8 mov QWORD PTR [rbp-0x18],rax auto bar2 = reinterpret_cast<unsigned long*>(SOME_GLOBAL); 1025: 48 8b 05 d4 2f 00 00 mov rax,QWORD PTR [rip+0x2fd4] # 4000 <SOME_GLOBAL> 102c: 48 89 45 e0 mov QWORD PTR [rbp-0x20],rax return 0; 1030: b8 00 00 00 00 mov eax,0x0 1035: 5d pop rbp 1036: c3 ret clang++-16 -c -g -fpie -o foo.o foo.cpp clang++-16 -c -g -fpie -o bar.o bar.cpp ld.lld-16 -pie -o got foo.o bar.o clang++-16 --version Debian clang version 16.0.6 (6) Target: x86_64-pc-linux-gnu Thread model: posix InstalledDir: /usr/bin objdump -M intel -DS -j .text got got: file format elf64-x86-64 Disassembly of section .text: 0000000000001290 <main>: extern unsigned long _GLOBAL_OFFSET_TABLE_ []; extern unsigned long SOME_GLOBAL; int main() { 1290: 55 push rbp 1291: 48 89 e5 mov rbp,rsp 1294: c7 45 fc 00 00 00 00 mov DWORD PTR [rbp-0x4],0x0 auto foo1 = reinterpret_cast<unsigned long*>(&_GLOBAL_OFFSET_TABLE_); 129b: 48 8b 05 c6 20 00 00 mov rax,QWORD PTR [rip+0x20c6] # 3368 <_GLOBAL_OFFSET_TABLE_> 12a2: 48 89 45 f0 mov QWORD PTR [rbp-0x10],rax auto foo2 = reinterpret_cast<unsigned long*>( _GLOBAL_OFFSET_TABLE_); 12a6: 48 8b 05 bb 20 00 00 mov rax,QWORD PTR [rip+0x20bb] # 3368 <_GLOBAL_OFFSET_TABLE_> 12ad: 48 89 45 e8 mov QWORD PTR [rbp-0x18],rax auto bar1 = &SOME_GLOBAL; 12b1: 48 8d 05 a8 20 00 00 lea rax,[rip+0x20a8] # 3360 <SOME_GLOBAL> 12b8: 48 89 45 e0 mov QWORD PTR [rbp-0x20],rax auto bar2 = reinterpret_cast<unsigned long*>(SOME_GLOBAL); 12bc: 48 8d 05 9d 20 00 00 lea rax,[rip+0x209d] # 3360 <SOME_GLOBAL> 12c3: 48 8b 00 mov rax,QWORD PTR [rax] 12c6: 48 89 45 d8 mov QWORD PTR [rbp-0x28],rax return 0; 12ca: 31 c0 xor eax,eax 12cc: 5d pop rbp 12cd: c3 ret 12ce: cc int3 12cf: cc int3 -
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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,24 @@ #CC = /home/justin/.local/lib/jsix/toolchains/llvm-13/bin/clang++ #LD = /home/justin/.local/lib/jsix/toolchains/llvm-13/bin/ld.lld #CC = g++ #LD = ld #CC = clang++-13 #LD = clang++-13 #LD = ld.lld-13 CC = clang++-16 LD = ld.lld-16 got: foo.o bar.o ${LD} -pie -o $@ $^ %.o: %.cpp ${CC} -c -g -fpie -o $@ $^ dump: got ${CC} --version objdump -M intel -DS -j .text $^ clean: -rm *.o got .PHONY: rip clean This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1 @@ unsigned long SOME_GLOBAL = 123; This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,12 @@ extern unsigned long _GLOBAL_OFFSET_TABLE_ []; extern unsigned long SOME_GLOBAL; int main() { auto foo1 = reinterpret_cast<unsigned long*>(&_GLOBAL_OFFSET_TABLE_); auto foo2 = reinterpret_cast<unsigned long*>( _GLOBAL_OFFSET_TABLE_); auto bar1 = &SOME_GLOBAL; auto bar2 = reinterpret_cast<unsigned long*>(SOME_GLOBAL); return 0; }