Re: [Mspgcc-users] relocation error
Hi David, .text .equ link,0 .word link .equ link, . .word link test.S:7: Error: redefined symbol cannot be used on reloc The error message is occurring because of a limitation of the assembler. For any given symbol it only maintains one value. Redefining the symbol (and then using it) is OK provided that the new value is absolute, but if it is something that the assembler cannot compute at assemble-time you get this error message. It works just fine on my old msp430-gcc. aka: Is there something I am doing wrong or did someone break the assembler? Break - no, change yes. The problem is that the linker now performs some code optimizations (referred to as relaxations) such as converting: jnz $+6 br label into: jz label provided that label is within range of the JZ instruction. But this means that the *size* of the .text section can change, and so any value that is PC-relative has to be computed by the linker, not the assembler. What happened with the old msp430-gcc assembler was that it was able to convert: .text .equ link, 0 .word link .equ link, . .word link into: .text .word 0 .word .text + 2 ie it replaced references to link with references to an absolute value and a section relative value. But the new assembler cannot do this as .text + 2 might no longer be the correct value for that location. So - what can you do ? Well, if you do not need these headers to be in the .text section then you can just move them to the .data section: .data .equ link, 0 .word link .equ link, . .word link This assembles just fine. (The assembler knows that the linker will not change the size of the .data section so it is free to replace symbol references with section relative references). Or you could use multiple symbols, rather than just redefining the same symbol. For example: .macro foo start=0 .ifstart == 1 .equ link\@, 0 .else .equ link\@, . .endif .word link\@ .endm .text .globl main main: foo 1 foo foo 0 This creates lots of symbols called link when is the invocation count of the foo macro. I hope that this helps. Cheers Nick -- Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=190641631iu=/4140/ostg.clktrk ___ Mspgcc-users mailing list Mspgcc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mspgcc-users
[Mspgcc-users] relocation error
Here is a puzzler. I have been fiddling with a version of Camelforth for the FRAM parts in an ill fated attempt to port it to the MSP430FR5969. The original code is for the IAR tools but I use gcc. After much gnashing of teeth and assorted hacking I have an error that I don't know how to fix or even if it can be fixed. The code uses a few macros to automate production of FORTH headers and the trouble is with the link field which creates a linked list of headers. Cutting it down to a small program that recreates the error: .text .globl main main: .equ link,0 .word link .equ link, . .word link .equ link, . .end test.S:7: Error: redefined symbol cannot be used on reloc Line 7 being the second .word link The really interesting thing is that while this fails on the newfangled TI version of msp430-elf-gcc, aka: msp430-elf-gcc (GCC) 4.9.1 20140707 (prerelease (msp430-14r1-167)) (GNUPro 14r1) It works just fine on my old msp430-gcc. aka: msp430-gcc (GCC) 4.6.4 20130412 (mspgcc LTS 20120406 unpatched) Is there something I am doing wrong or did someone break the assembler? -- David W. Schultz http://home.earthlink.net/~david.schultz Returned for Regrooving -- Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=190641631iu=/4140/ostg.clktrk ___ Mspgcc-users mailing list Mspgcc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mspgcc-users
Re: [Mspgcc-users] relocation error
Just a request, when reporting errors against the assembler, please give the assembler's version number, not the compiler's version number: $ msp430-elf-as --version GNU assembler (GNU Binutils) 2.25.51.20150212 FWIW I've reproduced this with the FSF assembler reporte above, which is the binutils development trunk version. Also FWIW, I think defining one symbol to have two values is a bad idea... -- Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=190641631iu=/4140/ostg.clktrk ___ Mspgcc-users mailing list Mspgcc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mspgcc-users
