“ -c”选项对Swift编译器（swiftc）有什么作用？

Question

我注意到swiftc中有“ -c”选项，该选项有什么作用？

  

swiftc ... -c ....

是否有关于此的正式文件？我在man，--help或在线上都找不到它：（

Answer 1

-c是-emit-object：

$ swiftc --help
OVERVIEW: Swift compiler

USAGE: swiftc [options] 

MODES:
  -dump-ast              Parse and type-check input file(s) and dump AST(s)
  -dump-parse            Parse input file(s) and dump AST(s)
  -dump-scope-maps 
                         Parse and type-check input file(s) and dump the scope map(s)
  -dump-type-info        Output YAML dump of fixed-size types from all imported modules
  -dump-type-refinement-contexts
                         Type-check input file(s) and dump type refinement contexts(s)
  -emit-assembly         Emit assembly file(s) (-S)
  -emit-bc               Emit LLVM BC file(s)
  -emit-executable       Emit a linked executable
  -emit-imported-modules Emit a list of the imported modules
  -emit-ir               Emit LLVM IR file(s)
  -emit-library          Emit a linked library
  -emit-object           Emit object file(s) (-c)
  -emit-sibgen           Emit serialized AST + raw SIL file(s)
  -emit-sib              Emit serialized AST + canonical SIL file(s)
  -emit-silgen           Emit raw SIL file(s)
  -emit-sil              Emit canonical SIL file(s)
  -index-file            Produce index data for a source file
  -parse                 Parse input file(s)
  -print-ast             Parse and type-check input file(s) and pretty print AST(s)
  -resolve-imports       Parse and resolve imports in input file(s)
  -typecheck             Parse and type-check input file(s)