Add option to allocate global variables and heap on stack#194
Merged
laurenthuberdeau merged 9 commits intomainfrom May 12, 2025
Merged
Add option to allocate global variables and heap on stack#194laurenthuberdeau merged 9 commits intomainfrom
laurenthuberdeau merged 9 commits intomainfrom
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Context
#152 moved the global variables to a mmap region, but some systems don't support that system call. With pnut-exe's one-pass mode, the code buffer doesn't get too large when compiling TCC, so statically allocated buffers (and other global variables) can be placed on the stack.
See fosslinux/live-bootstrap#524 (comment) for more context.
Concern
While the code buffer can be relatively small, other statically allocated buffers take up a lot of space. In particular, the string pool and heap buffers since they are never collected and grow proportional to the input program size. To compile TCC it may be required to increase the stack size limit even in one-pass mode.