* `nim doc --backend:js|cpp...`
`nim doc --doccmd:'-d:foo --threads:on'`
`nim r --backend:cpp...` (implies --run --usenimcache)
* --usenimcache works with all targets
* --docCmd:skip now skips compiling snippets; 50X speedup for doc/manual.rst
* system/gc: don't export markStackAndRegisters
* compiler/cgen: unexport internal symbols
As these functions are Nim-specific walkaround against C's optimization
schemes, they don't serve any purpose being exported.
* compiler/cgen: don't export global var unless marked
* compiler/ccgthreadvars: don't export threadvar unless marked
* tests/dll/visibility: also check for exports
This ensure that these changes don't break manual exports.
* compiler/cgen: hide all variables created for constants
* compiler/ccgtypes: don't export RTTI variables
* compiler/ccgexprs: make all complex const static
* nimbase.h: fix export for windows
* compiler/cgen, ccgthreadvars: export variables correctly
For C/C++ variables, `extern` means that the variable is defined in an
another unit. Added a new N_LIB_EXPORT_VAR to correctly export
variables.
This implements "deterministic" exception handling for Nim based on goto instead of setjmp. This means raising an exception is much cheaper than in C++'s table based implementations. Supports hard realtime systems. Default for --gc:arc and the C target because it's generally a good idea and arc is all about deterministic behavior.
Note: This implies that fatal runtime traps are not catchable anymore! This needs to be documented.
