Fix gcc warnings in C backend #302
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- prepare for changes to the select const tests causing problems compiling with the gcc backend - the test will generate a very large C listing (250K+ LOC with debugging enabled) with most of the asserts in a single procedure - with debug symbols enabled, gcc can run out of memory overflowing the symbol hash tables - and the test is very taxing on the gcc optimizer (-O1 or higher) resulting in a very slow compile time
- prepare for changes to the select const tests causing problems compiling with the gcc backend - the test will generate a very large C listing (250K+ LOC with debugging enabled) with most of the asserts in a single procedure - with debug symbols enabled, gcc can run out of memory overflowing the symbol hash tables - and the test is very taxing on the gcc optimizer (-O1 or higher) resulting in a very slow compile time
…an 128 characters - fixes github # 298: -Wc has a limit of 128 characters - previously fbc used fixed length strings of 128 bytes to hold the options to as, gcc, and ld - now uses variable length string instead
…higher optimizations - see github # 217 - warning: array subscript -1 is outside array bounds - caused by fbc's optimization of non-zero lower bound arrays - fbc calculates a kind of virtual pointer of where the array(0,..) element would be and then computes element addresses from that - this optimization in fbc saves some computations when accessing array elements but the translation to C is technically undefined behaviour - fixed (for now) by casting the address to the equivalent of intptr_t in C. (FB_DATATYPE_INTEGER).
- it's deprecated in newer gcc versions and silently ignored in older versions - gcc requires a valid stack to preserve registers and if the asm code clobbers esp/rsp then there is no way to get it back after esp/rsp changes to something else. - User is always responsoble for handling the stack registers.
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Fixes #298 -Wc has a limit of 128 characters
Fixes #217 warning: array subscript -1 is outside array bounds
Fixes gcc warning for esp/rsp in the listing of clobbered registers (now deprecated) by removing esp/rsp from the clobber list.
Fixes really slow compile of tests/compound/select_const.bas by splitting single test procedure in to multiple test procedures