1OCAMLC(1) General Commands Manual OCAMLC(1)
2
6 ocamlc - The OCaml bytecode compiler
7
10 ocamlc [ options ] filename ...
11 ocamlc.opt [ options ] filename ...
13
16 The OCaml bytecode compiler ocamlc(1) compiles OCaml source files to
17 bytecode object files and links these object files to produce stand‐
18 alone bytecode executable files. These executable files are then run
19 by the bytecode interpreter ocamlrun(1).
20 The ocamlc(1) command has a command-line interface similar to the one
22 of most C compilers. It accepts several types of arguments and pro‐
23 cesses them sequentially, after all options have been processed:
24 Arguments ending in .mli are taken to be source files for compilation
26 unit interfaces. Interfaces specify the names exported by compilation
27 units: they declare value names with their types, define public data
28 types, declare abstract data types, and so on. From the file x.mli, the
29 ocamlc(1) compiler produces a compiled interface in the file x.cmi.
30 Arguments ending in .ml are taken to be source files for compilation
32 unit implementations. Implementations provide definitions for the names
33 exported by the unit, and also contain expressions to be evaluated for
34 their side-effects. From the file x.ml, the ocamlc(1) compiler pro‐
35 duces compiled object bytecode in the file x.cmo.
36 If the interface file x.mli exists, the implementation x.ml is checked
38 against the corresponding compiled interface x.cmi, which is assumed to
39 exist. If no interface x.mli is provided, the compilation of x.ml pro‐
40 duces a compiled interface file x.cmi in addition to the compiled ob‐
41 ject code file x.cmo. The file x.cmi produced corresponds to an inter‐
42 face that exports everything that is defined in the implementation
43 x.ml.
44 Arguments ending in .cmo are taken to be compiled object bytecode.
46 These files are linked together, along with the object files obtained
47 by compiling .ml arguments (if any), and the OCaml standard library, to
48 produce a standalone executable program. The order in which .cmo and.ml
49 arguments are presented on the command line is relevant: compilation
50 units are initialized in that order at run-time, and it is a link-time
51 error to use a component of a unit before having initialized it. Hence,
52 a given x.cmo file must come before all .cmo files that refer to the
53 unit x.
54 Arguments ending in .cma are taken to be libraries of object bytecode.
56 A library of object bytecode packs in a single file a set of object
57 bytecode files (.cmo files). Libraries are built with ocamlc -a (see
58 the description of the -a option below). The object files contained in
59 the library are linked as regular .cmo files (see above), in the order
60 specified when the .cma file was built. The only difference is that if
61 an object file contained in a library is not referenced anywhere in the
62 program, then it is not linked in.
63 Arguments ending in .c are passed to the C compiler, which generates a
65 .o object file. This object file is linked with the program if the
66 -custom flag is set (see the description of -custom below).
67 Arguments ending in .o or .a are assumed to be C object files and li‐
69 braries. They are passed to the C linker when linking in -custom mode
70 (see the description of -custom below).
71 Arguments ending in .so are assumed to be C shared libraries (DLLs).
73 During linking, they are searched for external C functions referenced
74 from the OCaml code, and their names are written in the generated byte‐
75 code executable. The run-time system ocamlrun(1) then loads them dy‐
76 namically at program start-up time.
77 The output of the linking phase is a file containing compiled bytecode
79 that can be executed by the OCaml bytecode interpreter: the command
80 ocamlrun(1). If caml.out is the name of the file produced by the link‐
81 ing phase, the command ocamlrun caml.out arg1 arg2 ... argn executes
82 the compiled code contained in caml.out, passing it as arguments the
83 character strings arg1 to argn. (See ocamlrun(1) for more details.)
84 On most systems, the file produced by the linking phase can be run di‐
86 rectly, as in: ./caml.out arg1 arg2 ... argn. The produced file has
87 the executable bit set, and it manages to launch the bytecode inter‐
88 preter by itself.
89 ocamlc.opt is the same compiler as ocamlc, but compiled with the na‐
91 tive-code compiler ocamlopt(1). Thus, it behaves exactly like ocamlc,
92 but compiles faster. ocamlc.opt may not be available in all installa‐
93 tions of OCaml.
94
97 The following command-line options are recognized by ocamlc(1).
98 -a Build a library (.cma file) with the object files (.cmo files)
100 given on the command line, instead of linking them into an exe‐
101 cutable file. The name of the library must be set with the -o
102 option.
103 If -custom, -cclib or -ccopt options are passed on the command
105 line, these options are stored in the resulting .cma library.
106 Then, linking with this library automatically adds back the
107 -custom, -cclib and -ccopt options as if they had been provided
108 on the command line, unless the -noautolink option is given. Ad‐
109 ditionally, a substring $CAMLORIGIN inside a -ccopt options
110 will be replaced by the full path to the .cma library, excluding
111 the filename. -absname Show absolute filenames in error mes‐
112 sages.
113 -annot Deprecated since 4.11. Please use -bin-annot instead.
115 -bin-annot
117 Dump detailed information about the compilation (types, bind‐
118 ings, tail-calls, etc) in binary format. The information for
119 file src.ml is put into file src.cmt. In case of a type error,
120 dump all the information inferred by the type-checker before the
121 error. The annotation files produced by -bin-annot contain more
122 information and are much more compact than the files produced by
123 -annot.
124 -c Compile only. Suppress the linking phase of the compilation.
126 Source code files are turned into compiled files, but no exe‐
127 cutable file is produced. This option is useful to compile mod‐
128 ules separately.
129 -cc ccomp
131 Use ccomp as the C linker when linking in "custom runtime" mode
132 (see the -custom option) and as the C compiler for compiling .c
133 source files.
134 -cclib -llibname
136 Pass the -llibname option to the C linker when linking in "cus‐
137 tom runtime" mode (see the -custom option). This causes the
138 given C library to be linked with the program.
139 -ccopt option
141 Pass the given option to the C compiler and linker, when linking
142 in "custom runtime" mode (see the -custom option). For instance,
143 -ccopt -Ldir causes the C linker to search for C libraries in
144 directory dir.
145 -color mode
147 Enable or disable colors in compiler messages (especially warn‐
148 ings and errors). The following modes are supported:
149 auto use heuristics to enable colors only if the output supports
151 them (an ANSI-compatible tty terminal);
152 always enable colors unconditionally;
154 never disable color output.
156 The environment variable "OCAML_COLOR" is considered if -color
158 is not provided. Its values are auto/always/never as above.
159 If -color is not provided, "OCAML_COLOR" is not set and the en‐
161 vironment variable "NO_COLOR" is set, then color output is dis‐
162 abled. Otherwise, the default setting is auto, and the current
163 heuristic checks that the "TERM" environment variable exists and
164 is not empty or "dumb", and that isatty(stderr) holds.
165 -error-style mode
168 Control the way error messages and warnings are printed. The
169 following modes are supported:
170 short only print the error and its location;
172 contextual like "short", but also display the source code snip‐
174 pet corresponding to the location of the error.
175 The default setting is contextual.
177 The environment variable "OCAML_ERROR_STYLE" is considered if
179 -error-style is not provided. Its values are short/contextual as
180 above.
181 -compat-32
184 Check that the generated bytecode executable can run on 32-bit
185 platforms and signal an error if it cannot. This is useful when
186 compiling bytecode on a 64-bit machine.
187 -config
189 Print the version number of ocamlc(1) and a detailed summary of
190 its configuration, then exit.
191 -config-var
193 Print the value of a specific configuration variable from the
194 -config output, then exit. If the variable does not exist, the
195 exit code is non-zero.
196 -custom
198 Link in "custom runtime" mode. In the default linking mode, the
199 linker produces bytecode that is intended to be executed with
200 the shared runtime system, ocamlrun(1). In the custom runtime
201 mode, the linker produces an output file that contains both the
202 runtime system and the bytecode for the program. The resulting
203 file is larger, but it can be executed directly, even if the
204 ocamlrun(1) command is not installed. Moreover, the "custom run‐
205 time" mode enables linking OCaml code with user-defined C func‐
206 tions.
207 Never use the strip(1) command on executables produced by
209 ocamlc -custom, this would remove the bytecode part of the exe‐
210 cutable.
211 Security warning: never set the "setuid" or "setgid" bits on ex‐
213 ecutables produced by ocamlc -custom, this would make them vul‐
214 nerable to attacks.
215 -depend ocamldep-args
217 Compute dependencies, as ocamldep would do.
218 -dllib -llibname
220 Arrange for the C shared library dlllibname.so to be loaded dy‐
221 namically by the run-time system ocamlrun(1) at program start-up
222 time.
223 -dllpath dir
225 Adds the directory dir to the run-time search path for shared C
226 libraries. At link-time, shared libraries are searched in the
227 standard search path (the one corresponding to the -I option).
228 The -dllpath option simply stores dir in the produced executable
229 file, where ocamlrun(1) can find it and use it.
230 -for-pack module-path
232 Generate an object file (.cmo file) that can later be included
233 as a sub-module (with the given access path) of a compilation
234 unit constructed with -pack. For instance,
235 ocamlc -for-pack P -c A.ml will generate a.cmo that can later be
236 used with ocamlc -pack -o P.cmo a.cmo. Note: you can still pack
237 a module that was compiled without -for-pack but in this case
238 exceptions will be printed with the wrong names.
239 -g Add debugging information while compiling and linking. This op‐
241 tion is required in order to be able to debug the program with
242 ocamldebug(1) and to produce stack backtraces when the program
243 terminates on an uncaught exception.
244 -i Cause the compiler to print all defined names (with their in‐
246 ferred types or their definitions) when compiling an implementa‐
247 tion (.ml file). No compiled files (.cmo and .cmi files) are
248 produced. This can be useful to check the types inferred by the
249 compiler. Also, since the output follows the syntax of inter‐
250 faces, it can help in writing an explicit interface (.mli file)
251 for a file: just redirect the standard output of the compiler to
252 a .mli file, and edit that file to remove all declarations of
253 unexported names.
254 -I directory
256 Add the given directory to the list of directories searched for
257 compiled interface files (.cmi), compiled object code files
258 (.cmo), libraries (.cma), and C libraries specified with
259 -cclib -lxxx . By default, the current directory is searched
260 first, then the standard library directory. Directories added
261 with -I are searched after the current directory, in the order
262 in which they were given on the command line, but before the
263 standard library directory. See also option -nostdlib.
264 If the given directory starts with +, it is taken relative to
266 the standard library directory. For instance, -I +compiler-libs
267 adds the subdirectory compiler-libs of the standard library to
268 the search path.
269 -impl filename
271 Compile the file filename as an implementation file, even if its
272 extension is not .ml.
273 -intf filename
275 Compile the file filename as an interface file, even if its ex‐
276 tension is not .mli.
277 -intf-suffix string
279 Recognize file names ending with string as interface files (in‐
280 stead of the default .mli).
281 -keep-docs
283 Keep documentation strings in generated .cmi files.
284 -keep-locs
286 Keep locations in generated .cmi files.
287 -labels
289 Labels are not ignored in types, labels may be used in applica‐
290 tions, and labelled parameters can be given in any order. This
291 is the default.
292 -linkall
294 Force all modules contained in libraries to be linked in. If
295 this flag is not given, unreferenced modules are not linked in.
296 When building a library (option -a), setting the -linkall option
297 forces all subsequent links of programs involving that library
298 to link all the modules contained in the library. When compil‐
299 ing a module (option -c), setting the -linkall option ensures
300 that this module will always be linked if it is put in a library
301 and this library is linked.
302 -make-runtime
304 Build a custom runtime system (in the file specified by option
305 -o) incorporating the C object files and libraries given on the
306 command line. This custom runtime system can be used later to
307 execute bytecode executables produced with the option
308 ocamlc -use-runtime runtime-name.
309 -match-context-rows
311 Set number of rows of context used during pattern matching com‐
312 pilation. Lower values cause faster compilation, but less opti‐
313 mized code. The default value is 32.
314 -no-alias-deps
316 Do not record dependencies for module aliases.
317 -no-app-funct
319 Deactivates the applicative behaviour of functors. With this op‐
320 tion, each functor application generates new types in its result
321 and applying the same functor twice to the same argument yields
322 two incompatible structures.
323 -noassert
325 Do not compile assertion checks. Note that the special form as‐
326 sert false is always compiled because it is typed specially.
327 This flag has no effect when linking already-compiled files.
328 -noautolink
330 When linking .cma libraries, ignore -custom, -cclib and -ccopt
331 options potentially contained in the libraries (if these options
332 were given when building the libraries). This can be useful if
333 a library contains incorrect specifications of C libraries or C
334 options; in this case, during linking, set -noautolink and pass
335 the correct C libraries and options on the command line.
336 -nolabels
338 Ignore non-optional labels in types. Labels cannot be used in
339 applications, and parameter order becomes strict.
340 -nostdlib
342 Do not automatically add the standard library directory to the
343 list of directories searched for compiled interface files
344 (.cmi), compiled object code files (.cmo), libraries (.cma), and
345 C libraries specified with -cclib -lxxx . See also option -I.
346 -o exec-file
348 Specify the name of the output file produced by the linker. The
349 default output name is a.out, in keeping with the Unix tradi‐
350 tion. If the -a option is given, specify the name of the library
351 produced. If the -pack option is given, specify the name of the
352 packed object file produced. If the -output-obj or -output-com‐
353 plete-obj option is given, specify the name of the output file
354 produced. This can also be used when compiling an interface or
355 implementation file, without linking, in which case it sets the
356 name of the cmi or cmo file, and also sets the module name to
357 the file name up to the first dot.
358 -opaque
360 Interface file compiled with this option are marked so that
361 other compilation units depending on it will not rely on any im‐
362 plementation details of the compiled implementation. The native
363 compiler will not access the .cmx file of this unit -- nor warn
364 if it is absent. This can improve speed of compilation, for both
365 initial and incremental builds, at the expense of performance of
366 the generated code.
367 -open module
369 Opens the given module before processing the interface or imple‐
370 mentation files. If several -open options are given, they are
371 processed in order, just as if the statements open! module1;;
372 ... open! moduleN;; were added at the top of each file.
373 -output-obj
375 Cause the linker to produce a C object file instead of a byte‐
376 code executable file. This is useful to wrap OCaml code as a C
377 library, callable from any C program. The name of the output ob‐
378 ject file must be set with the -o option. This option can also
379 be used to produce a C source file (.c extension) or a compiled
380 shared/dynamic library (.so extension).
381 -output-complete-obj
383 Same as -output-obj except when creating an object file where it
384 includes the runtime and autolink libraries.
385 -pack Build a bytecode object file (.cmo file) and its associated com‐
387 piled interface (.cmi) that combines the object files given on
388 the command line, making them appear as sub-modules of the out‐
389 put .cmo file. The name of the output .cmo file must be given
390 with the -o option. For instance,
391 ocamlc -pack -o p.cmo a.cmo b.cmo c.cmo generates compiled files
392 p.cmo and p.cmi describing a compilation unit having three sub-
393 modules A, B and C, corresponding to the contents of the object
394 files a.cmo, b.cmo and c.cmo. These contents can be referenced
395 as P.A, P.B and P.C in the remainder of the program.
396 -pp command
398 Cause the compiler to call the given command as a preprocessor
399 for each source file. The output of command is redirected to an
400 intermediate file, which is compiled. If there are no compila‐
401 tion errors, the intermediate file is deleted afterwards. The
402 name of this file is built from the basename of the source file
403 with the extension .ppi for an interface (.mli) file and .ppo
404 for an implementation (.ml) file.
405 -ppx command
407 After parsing, pipe the abstract syntax tree through the pre‐
408 processor command. The module Ast_mapper(3) implements the ex‐
409 ternal interface of a preprocessor.
410 -principal
412 Check information path during type-checking, to make sure that
413 all types are derived in a principal way. When using labelled
414 arguments and/or polymorphic methods, this flag is required to
415 ensure future versions of the compiler will be able to infer
416 types correctly, even if internal algorithms change. All pro‐
417 grams accepted in -principal mode are also accepted in the de‐
418 fault mode with equivalent types, but different binary signa‐
419 tures, and this may slow down type checking; yet it is a good
420 idea to use it once before publishing source code.
421 -rectypes
423 Allow arbitrary recursive types during type-checking. By de‐
424 fault, only recursive types where the recursion goes through an
425 object type are supported. Note that once you have created an
426 interface using this flag, you must use it again for all depen‐
427 dencies.
428 -runtime-variant suffix
430 Add suffix to the name of the runtime library that will be used
431 by the program. If OCaml was configured with option -with-de‐
432 bug-runtime, then the d suffix is supported and gives a debug
433 version of the runtime.
434 -stop-after pass
436 Stop compilation after the given compilation pass. The currently
437 supported passes are: parsing, typing.
438 -safe-string
440 Enforce the separation between types string and bytes, thereby
441 making strings read-only. This is the default.
442 -short-paths
444 When a type is visible under several module-paths, use the
445 shortest one when printing the type's name in inferred inter‐
446 faces and error and warning messages.
447 -strict-sequence
449 Force the left-hand part of each sequence to have type unit.
450 -unboxed-types
452 When a type is unboxable (i.e. a record with a single argument
453 or a concrete datatype with a single constructor of one argu‐
454 ment) it will be unboxed unless annotated with [@@ocaml.boxed].
455 -no-unboxed-types
457 When a type is unboxable it will be boxed unless annotated with
458 [@@ocaml.unboxed]. This is the default.
459 -unsafe
461 Turn bound checking off for array and string accesses (the
462 v.(i)ands.[i] constructs). Programs compiled with -unsafe are
463 therefore slightly faster, but unsafe: anything can happen if
464 the program accesses an array or string outside of its bounds.
465 -unsafe-string
467 Identify the types string and bytes, thereby making strings
468 writable. This is intended for compatibility with old source
469 code and should not be used with new software.
470 -use-runtime runtime-name
472 Generate a bytecode executable file that can be executed on the
473 custom runtime system runtime-name, built earlier with
474 ocamlc -make-runtime runtime-name.
475 -v Print the version number of the compiler and the location of the
477 standard library directory, then exit.
478 -verbose
480 Print all external commands before they are executed, in partic‐
481 ular invocations of the C compiler and linker in -custom mode.
482 Useful to debug C library problems.
483 -vnum or -version
485 Print the version number of the compiler in short form (e.g.
486 "3.11.0"), then exit.
487 -w warning-list
489 Enable, disable, or mark as fatal the warnings specified by the
490 argument warning-list.
491 Each warning can be enabled or disabled, and each warning can be
493 fatal or non-fatal. If a warning is disabled, it isn't dis‐
494 played and doesn't affect compilation in any way (even if it is
495 fatal). If a warning is enabled, it is displayed normally by
496 the compiler whenever the source code triggers it. If it is en‐
497 abled and fatal, the compiler will also stop with an error after
498 displaying it.
499 The warning-list argument is either a mnemonic warning specifier
501 or a sequence of single character warning specifiers, with no
502 separators between them. A mnemonic warning specifier is one of
503 the following
504 +name Enable warning name.
506 -name Disable warning name.
508 @name Enable and mark as fatal warning name.
510 A single character warning specifier is one of the following:
512 +num Enable warning number num.
514 -num Disable warning number num.
516 @num Enable and mark as fatal warning number num.
518 +num1..num2 Enable all warnings between num1 and num2 (inclu‐
520 sive).
521 -num1..num2 Disable all warnings between num1 and num2 (inclu‐
523 sive).
524 @num1..num2 Enable and mark as fatal all warnings between num1
526 and num2 (inclusive).
527 +letter Enable the set of warnings corresponding to letter.
529 The letter may be uppercase or lowercase.
530 -letter Disable the set of warnings corresponding to letter.
532 The letter may be uppercase or lowercase.
533 @letter Enable and mark as fatal the set of warnings corre‐
535 sponding to letter. The letter may be uppercase or lowercase.
536 uppercase-letter Enable the set of warnings corresponding to
538 uppercase-letter.
539 lowercase-letter Disable the set of warnings corresponding to
541 lowercase-letter.
542 The warning numbers and mnemonic names are as follows.
544 1 [comment-start]
546 Suspicious-looking start-of-comment mark.
547 2 [comment-not-end]
549 Suspicious-looking end-of-comment mark.
550 3
552 Deprecated feature.
553 4 [fragile-match]
555 Fragile pattern matching: matching that will remain complete
556 even if additional constructors are added to one of the variant
557 types matched.
558 5 [ignored-partial-application]
560 Partially applied function: expression whose result has function
561 type and is ignored.
562 6 [labels-omitted]
564 Label omitted in function application.
565 7 [method-override]
567 Method overridden without using the "method!" keyword.
568 8 [partial-match]
570 Partial match: missing cases in pattern-matching.
571 9 [missing-record-field-pattern]
573 Missing fields in a record pattern.
574 10 [non-unit-statement]
576 Expression on the left-hand side of a sequence that doesn't have
577 type unit (and that is not a function, see warning number 5).
578 11 [redundant-case]
580 Redundant case in a pattern matching (unused match case).
581 12 [redundant-subpat]
583 Redundant sub-pattern in a pattern-matching.
584 13 [instance-variable-override]
586 Override of an instance variable.
587 14 [illegal-backslash]
589 Illegal backslash escape in a string constant.
590 15 [implicit-public-methods]
592 Private method made public implicitly.
593 16 [unerasable-optional-argument]
595 Unerasable optional argument.
596 17 [undeclared-virtual-method]
598 Undeclared virtual method.
599 18 [not-principal]
601 Non-principal type.
602 19 [non-principal-labels]
604 Type without principality.
605 20 [ignored-extra-argument]
607 Unused function argument.
608 21 [nonreturning-statement]
610 Non-returning statement.
611 22 [preprocessor]
613 Preprocessor warning.
614 23 [useless-record-with]
616 Useless record with clause.
617 24 [bad-module-name]
619 Bad module name: the source file name is not a valid OCaml mod‐
620 ule name.
621 25
623 Deprecated: now part of warning 8.
624 26 [unused-var]
626 Suspicious unused variable: unused variable that is bound with
627 let or as, and doesn't start with an underscore (_) character.
628 27 [unused-var-strict]
630 Innocuous unused variable: unused variable that is not bound
631 with let nor as, and doesn't start with an underscore (_) char‐
632 acter.
633 28 [wildcard-arg-to-constant-constr]
635 A pattern contains a constant constructor applied to the under‐
636 score (_) pattern.
637 29 [eol-in-string]
639 A non-escaped end-of-line was found in a string constant. This
640 may cause portability problems between Unix and Windows.
641 30 [duplicate-definitions]
643 Two labels or constructors of the same name are defined in two
644 mutually recursive types.
645 31 [module-linked-twice]
647 A module is linked twice in the same executable.
648 32 [unused-value-declaration]
650 Unused value declaration.
651 33 [unused-open]
653 Unused open statement.
654 34 [unused-type-declaration]
656 Unused type declaration.
657 35 [unused-for-index]
659 Unused for-loop index.
660 36 [unused-ancestor]
662 Unused ancestor variable.
663 37 [unused-constructor]
665 Unused constructor.
666 38 [unused-extension]
668 Unused extension constructor.
669 39 [unused-rec-flag]
671 Unused rec flag.
672 40 [name-out-of-scope]
674 Constructor or label name used out of scope.
675 41 [ambiguous-name]
677 Ambiguous constructor or label name.
678 42 [disambiguated-name]
680 Disambiguated constructor or label name.
681 43 [nonoptional-label]
683 Nonoptional label applied as optional.
684 44 [open-shadow-identifier]
686 Open statement shadows an already defined identifier.
687 45 [open-shadow-label-constructor]
689 Open statement shadows an already defined label or constructor.
690 46 [bad-env-variable]
692 Error in environment variable.
693 47 [attribute-payload]
695 Illegal attribute payload.
696 48 [eliminated-optional-arguments]
698 Implicit elimination of optional arguments.
699 49 [no-cmi-file]
701 Missing cmi file when looking up module alias.
702 50 [unexpected-docstring]
704 Unexpected documentation comment.
705 51 [wrong-tailcall-expectation]
707 Function call annotated with an incorrect @tailcall attribute
708 52 [fragile-literal-pattern]
710 Fragile constant pattern.
711 53 [misplaced-attribute]
713 Attribute cannot appear in this context.
714 54 [duplicated-attribute]
716 Attribute used more than once on an expression.
717 55 [inlining-impossible]
719 Inlining impossible.
720 56 [unreachable-case]
722 Unreachable case in a pattern-matching (based on type informa‐
723 tion).
724 57 [ambiguous-var-in-pattern-guard]
726 Ambiguous or-pattern variables under guard.
727 58 [no-cmx-file]
729 Missing cmx file.
730 59 [flambda-assignment-to-non-mutable-value]
733 Assignment on non-mutable value.
734 60 [unused-module]
736 Unused module declaration.
737 61 [unboxable-type-in-prim-decl]
739 Unannotated unboxable type in primitive declaration.
740 62 [constraint-on-gadt]
742 Type constraint on GADT type declaration.
743 63 [erroneous-printed-signature]
745 Erroneous printed signature.
746 64 [unsafe-array-syntax-without-parsing]
748 -unsafe used with a preprocessor returning a syntax tree.
749 65 [redefining-unit]
751 Type declaration defining a new '()' constructor.
752 66 [unused-open-bang]
754 Unused open! statement.
755 67 [unused-functor-parameter]
757 Unused functor parameter.
758 68 [match-on-mutable-state-prevent-uncurry]
760 Pattern-matching depending on mutable state prevents the remain‐
761 ing arguments from being uncurried.
762 69 [unused-field]
764 Unused record field.
765 70 [missing-mli]
767 Missing interface file.
768 71 [unused-tmc-attribute]
770 Unused @tail_mod_cons attribute
771 72 [tmc-breaks-tailcall]
773 A tail call is turned into a non-tail call by the @tail_mod_cons
774 transformation.
775 The letters stand for the following sets of warnings. Any let‐
778 ter not mentioned here corresponds to the empty set.
779 A all warnings
781 C 1, 2
783 D 3
785 E 4
787 F 5
789 K 32, 33, 34, 35, 36, 37, 38, 39
791 L 6
793 M 7
795 P 8
797 R 9
799 S 10
801 U 11, 12
803 V 13
805 X 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 30
807 Y 26
809 Z 27
811 The default setting is
814 -w +a-4-7-9-27-29-30-32..42-44-45-48-50-60-66..70. Note that
815 warnings 5 and 10 are not always triggered, depending on the in‐
816 ternals of the type checker.
817 -warn-error warning-list
819 Mark as errors the warnings specified in the argument warn‐
820 ing-list. The compiler will stop with an error when one of
821 these warnings is emitted. The warning-list has the same mean‐
822 ing as for the -w option: a + sign (or an uppercase letter)
823 marks the corresponding warnings as fatal, a - sign (or a lower‐
824 case letter) turns them back into non-fatal warnings, and a @
825 sign both enables and marks as fatal the corresponding warnings.
826 Note: it is not recommended to use the -warn-error option in
828 production code, because it will almost certainly prevent com‐
829 piling your program with later versions of OCaml when they add
830 new warnings or modify existing warnings.
831 The default setting is -warn-error -a+31 (only warning 31 is fa‐
833 tal).
834 -warn-help
836 Show the description of all available warning numbers.
837 -where Print the location of the standard library, then exit.
839 -with-runtime
841 Include the runtime system in the generated program. This is the
842 default.
843 -without-runtime
845 The compiler does not include the runtime system (nor a refer‐
846 ence to it) in the generated program; it must be supplied sepa‐
847 rately.
848 - file Process file as a file name, even if it starts with a dash (-)
850 character.
851 -help or --help
853 Display a short usage summary and exit.
854
857 ocamlopt(1), ocamlrun(1), ocaml(1).
858 The OCaml user's manual, chapter "Batch compilation".
859 OCAMLC(1)