VMA is virtual memory address while LMA is load memory address. If both are not equal, which one of the addresses does linker consider while resolving symbols' addresses?
Let us consider a simple program test.c:
int i=10;
int main() {
return i++;
}
After compiling it to ELF-executable, dump the output sections. (I am compiling for AVR target using avr-gcc)
Sections:
Idx Name Size VMA LMA File off Algn
0 .text 00000040 00000000 00000000 00000074 2**1
CONTENTS, ALLOC, LOAD, READONLY, CODE
1 .data 00000002 00800060 00000040 000000b4 2**0
CONTENTS, ALLOC, LOAD, DATA
Notice the values in bold. VMA and LMA of .data section differ? Since 'i' is the only variable, what address will 'i' have? VMA or LMA ? When the text section is disassembled, what will be the address of memory accessed by instructions to read and write the value of variable 'i'?
Reference for linker script file: Linker Script Documentation
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