top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

Why stage1-gcc is not compiled with optimization?

0 votes
218 views

When I was building GCC, I found out that stage1-gcc is not compiled with optimization (such as -O2). So the compilation of stage2 is very slow. Is this intended or not? If not, did I made some mistakes in configure options and caused this?

posted Feb 22, 2017 by anonymous
Looking for an answer?  Promote on:
Facebook Share Button Twitter Share Button LinkedIn Share Button

Your answer

Preview
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
To avoid this verification in future, please log in or register.
Similar Questions
+1 vote
code optimization with gcc

My current compiler settings are 

arm-none-eabi-gcc -Wall -mfpu=fpv4-sp-d16 -mfloat-abi=softfp -fshort-double-mcpu=cortex-m4 -mthumb -Qn -Os -finstrument-functions -mlong-calls -c temp.c -o temp.o
so on for temp1, temp2... Etc

I am compiling multiple C files. and linker settings are

ld -r temp.o -o one.o
so on for temp1, temp2... Etc

I am linking multiple .O files. Also I am using linker script i.e link.txt (invoked externally as below)

ld -cref -Map map.txt -S -T link.txt -temp.o -lm -lc -lgcc
arm-none-eabi-gcc -Wall sample.o -O Firmware.abs

Now, At output I get .abs file of 140KB.

My Questions are
1. How to optimize (reduce size of .abs) by using compiler or linker specific options?
2. There are Number of NOT used global variables and Blank Function Calls in my C files (NO Dead Code!!!!). Is it possible to perform some link time optimization.
3. Please Elaborate as I am new to this, I have referred sites, gcc help and tried some "lto" options but NO reduction is size.
4. I also tried using -fdata-sections -ffunction-sections
But It has INCREASED my firmware.abs file size from KB to MB (yes it is MB!!!!) I also wondered WHY?
I am using codesourcery arm toolchain evaluation. It has gcc version 4.5.2

0 votes
GCC : What are all optimization flags present in gcc compiler ?

I am looking for detailed description of optimization flags that are provided by GCC compiler ?

+5 votes
How to disable GCC optimization

GCC is stripping the object file when nothing from the file is being used anywhere in the executable (even -o0 does nor help). We have to disable this feature of linker g++. could any one please help us to resolve this issue??

0 votes
static library unresolved symbols compiled using gcc

I'm inspecting a static library with nm, and I see that the tool provides me with the unresolved symbols of a file foo.o even though those symbols are defined in file zoo.o and both are included in the static library (ar rcs libmy.a zoo.o foo.o).

How can I ask nm to resolve these symbols if they can be found within the files of the archive and just report me about the other not resolved?

...