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memory corruption problem
- From: "Wilkes, John" <John dot Wilkes at amd dot com>
- To: "newlib at sourceware dot org" <newlib at sourceware dot org>
- Cc: "Wilkes, John" <John dot Wilkes at amd dot com>
- Date: Sat, 9 Jul 2016 17:45:52 +0000
- Subject: memory corruption problem
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I am using a gcc-6.1.0 and newlib-2.4.0 tool chain. FreeRTOS builds with this tool chain and runs all the FreeRTOS demos, so think the newlib port is pretty solid.
However, when running a bare metal program (no OS), I get some memory corruption; a critical variable is overwritten with garbage. I traced the problem to the stdout __FILE pointer.
It looks like the stdout __FILE struct is initialized in _sinit, and "__FILE *_stdout" in the _reent stuct points to the critical variable (i.e. same address). The trashed variable has a fixed address visible in "nm" output, so it doesn't move.
Where in the newlib code is the stdout __FILE struct allocated/created?
This is a new port with primitive debugging, i.e. no gdb support yet, and no shiny eclipse IDE.
Thanks for any help/insight/suggestions!
John Wilkes | AMD Research | email@example.com | office: +1 425.586.6412 (x26412)