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Hello,
Currently, I'm working on the transition of a project initially compiled with ARMCC (for an ARMv7 architecture) and now compiled with ARMCLANG (for an ARMv8 architecture).
With ARMLINK, I get the following error:
Error: L6244E: Load region LOAD_TTB address (0x0000f800) not aligned on a 16384 byte boundary.
Below is the scatter file sample:
LOAD_TTB 0xF800 0x4800 { CODE_TTB AlignExpr(+0, 0x4800) { ttb.o (+RO) } }
I haven't found any information (especially in the links below) on why this error occurs now and if this error is a source of faults when running a program. Or I can safely use “--diag_suppress=6244”.
Do you have a rough explanation to help me to understand, Why switching to ARMCLANG generates this error with ARMLINK?
In addition, can you highlight a related documentation?
Thanks in advance.
---
Arm Compiler for Embedded Errors and Warnings Reference Guide: https://developer.arm.com/documentation/100074/latest/
Arm Compiler armlink User Guide: https://developer.arm.com/documentation/dui0803/l/?lang=en
https://community.arm.com/support-forums/f/compilers-and-libraries-forum/54501/error-l6244e-region-not-aligned-on-cm33-secure-world-with-arm-v6-19-compiler
0x4800 is not a valid AlignExpr() value, it must be a power of 2. Hence the error message refers to 16384 (0x4000), which is 0x4800 rounded down to nearest 2^n.https://developer.arm.com/documentation/101754/0620/armlink-Reference/Scatter-File-Syntax/Expression-evaluation-in-scatter-files/AlignExpr-expr--align--function
The linker error presumably is then incurred as it cannot place your CODE_TTB execution region in a valid location within these parameters. How big is the code within ttb.o? (use "fromelf -z ttb.o").
Regards, Ronan
Thank you for your reply.
In a file ttb.c, three tables are declared with the following attribute “__attribute__((at(0xFC00)))” (Originally compiled with ARMCC). Following the documentation “Migration and Compatibility Guide“, I changed the attribute to “__attribute__((section(".ARM.__at_0xFC00")))“.
I then noticed that ARMLINK had added a PADDING zone in LOAD_TTB in place of one of the arrays with the attribute “__attribute__((section(".ARM.__at_0xFC00")))“. So I added "AlignExpr()" as suggested in the ARMLINK documentation « 8.12 Example of using expression evaluation in a scatter file to avoid padding »
If AlignExpr() is undesirable in my case, I have two questions:
1. Why does ARMLINK add a PAD section, knowing that this was not the case when the code was compiled with ARMCC?2. How can I avoid introducing a padding section?
Extract from the memory map provided by ARMLINK:
Load Region LOAD_TTB (Base: 0x0000f800, Size: 0x00004800, Max: 0x00004800, ABSOLUTE) Execution Region CODE_TTB (Base: 0x0000f800, Size: 0x00004800, Max: 0x00004800, ABSOLUTE) Base Addr Size Type Attr Idx E Section Name Object 0x0000f800 0x00000400 Data RO 134 .ARM.__at_0xF800 ttb.o 0x0000fc00 0x00000400 PAD 0x00010000 0x00004000 Data RO 132 .ARM.__at_0x10000 ttb.o Load Region LR$$.ARM.__at_0xF800 (Base: 0x0000f800, Size: 0x00000000, Max: 0x00000400, ABSOLUTE) Execution Region ER$$.ARM.__at_0xF800 (Base: 0x0000f800, Size: 0x00000000, Max: 0x00000400, ABSOLUTE, UNINIT) **** No section assigned to this execution region **** Load Region LR$$.ARM.__at_0xFC00 (Base: 0x0000fc00, Size: 0x00000400, Max: 0x00000400, ABSOLUTE) Execution Region ER$$.ARM.__at_0xFC00 (Base: 0x0000fc00, Size: 0x00000400, Max: 0x00000400, ABSOLUTE, UNINIT) Base Addr Size Type Attr Idx E Section Name Object 0x0000fc00 0x00000400 Data RO 133 .ARM.__at_0xFC00 ttb.o
To answer your question:
$ fromelf -z ttb.o
Could you share your ttb.c source code? It may be best to raise an 'official' support case from the support menu above, so that it can be shared privately to Arm (please reference this thread).
I don't understand what is happening, based on your description above.