[flang] Do not enable OpenMP by default, oops.

Original-commit: flang-compiler/f18@7a627ac040b07e9f03e0883e4b5680ec432ff98f
Reviewed-on: https://github.com/flang-compiler/f18/pull/130
Tree-same-pre-rewrite: false

[flang] Define LanguageFeatureControl, use it everywhere.

Original-commit: flang-compiler/f18@9a95107610c0d785c8b56576909ea4cf6efd5814
Reviewed-on: https://github.com/flang-compiler/f18/pull/130
Tree-same-pre-rewrite: false

[flang] Better language feature enablement and warnings.

Original-commit: flang-compiler/f18@359e4d2c600a31f26774a46f01b2a70fc62bc558
Reviewed-on: https://github.com/flang-compiler/f18/pull/130
Tree-same-pre-rewrite: false

[flang] Another SUBMODULE unparsing tweak, and restore buildability with gcc < 8.1

Original-commit: flang-compiler/f18@86b5db4b234da659702320a3c614f3f6b5ba3757
Reviewed-on: https://github.com/flang-compiler/f18/pull/130
Tree-same-pre-rewrite: false

[flang] Fix clang build warning in mod-file.cc

Original-commit: flang-compiler/f18@53ad3bd59cfcdfe2500a567a0892aca26bfb84da
Reviewed-on: https://github.com/flang-compiler/f18/pull/130
Tree-same-pre-rewrite: false

[flang] Address issue#125, flang-compiler/f18#115, and improve error recovery on previous issues.

Original-commit: flang-compiler/f18@98e26d6245e93e17520fc64be1eff3b4b7db5d9f
Reviewed-on: https://github.com/flang-compiler/f18/pull/130
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#131 from flang-compiler/tsk2

Update module file documentation

Original-commit: flang-compiler/f18@8981007d1c2093320cf671648ea139b20fefe9ae
Reviewed-on: https://github.com/flang-compiler/f18/pull/131

[flang] Update module file documentation

Address some review comments, add more information.

Original-commit: flang-compiler/f18@75c97b6f9bf6a5274e0e2398312587d92d3e0064
Reviewed-on: https://github.com/flang-compiler/f18/pull/131

[flang] Merge pull request flang-compiler/f18#127 from flang-compiler/tsk5

Use brace initialization with auto

Original-commit: flang-compiler/f18@f767ea2e1a0d1b1a39d6bcaee8559bddb0c624be
Reviewed-on: https://github.com/flang-compiler/f18/pull/127

[flang] Use brace initialization in tools/f18

Also reformat dump.cc.

Original-commit: flang-compiler/f18@1cc4fe278841b22437d4f3857b84e10dedbf71e5
Reviewed-on: https://github.com/flang-compiler/f18/pull/127

[flang] Use brace initialization in lib/semantics

Syntax only, no functional changes.

Original-commit: flang-compiler/f18@8cc9743c9cddbda0d93cb171d623277715c3c7e2
Reviewed-on: https://github.com/flang-compiler/f18/pull/127
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#129 from flang-compiler/tsk2

Fix test script portability problems.

Original-commit: flang-compiler/f18@e7f83218a310d02932a2429e8330ae3c48a3432d
Reviewed-on: https://github.com/flang-compiler/f18/pull/129

[flang] Fix test script portability problems.

Allow for bash anywhere on path.

Allow for utilites to be in /bin as well as /usr/bin.

Don't count on sed understanding '\t'.

The options to mktemp aren't portable. Instead just create a per-test
temp directory in the working directory (i.e. <build-dir>/test/semantics).
Setting the KEEP environment variable causes them all to be kept to help
in investigating failures.

Fixes flang-compiler/f18#128.

Original-commit: flang-compiler/f18@3736ceeca83965e3c9e282e92ddb6323523b9e5b
Reviewed-on: https://github.com/flang-compiler/f18/pull/129

[flang] Merge pull request flang-compiler/f18#126 from flang-compiler/tsk5

Implement writing of .mod files.

Original-commit: flang-compiler/f18@94c1f72fbdcd0c0f5c6e91ae907b9d54bbfb4721
Reviewed-on: https://github.com/flang-compiler/f18/pull/126

[flang] Handle VOLATILE or ASYNCHRONOUS added to use-associated entity

When a symbol is use-associated, the VOLATILE and ASYNCHRONOUS
attributes can be added. When that happens it must be recorded
in the .mod file.

Original-commit: flang-compiler/f18@44fa9e5ba4172f75abe4194e7f58b26a99646cdc
Reviewed-on: https://github.com/flang-compiler/f18/pull/126

[flang] Fix typo

Original-commit: flang-compiler/f18@242ff9d229c376fbff9942844af12c876bd3e13f
Reviewed-on: https://github.com/flang-compiler/f18/pull/126
Tree-same-pre-rewrite: false

[flang] Add a .mod file test with subprograms

The .mod file just contains the API. Test that prefixes and suffixes
on the declaration get correctly persisted.

Original-commit: flang-compiler/f18@eb2a6deb4fe12bae83fc3cb2366d056cf50cc9a5
Reviewed-on: https://github.com/flang-compiler/f18/pull/126
Tree-same-pre-rewrite: false

[flang] Initial documentation for .mod files

Original-commit: flang-compiler/f18@f1809b833f2d4265221677dcfb8b38577f6e69ba
Reviewed-on: https://github.com/flang-compiler/f18/pull/126
Tree-same-pre-rewrite: false

[flang] Add tests for .mod file writing

The source files contain the expected contents of generated .mod files.
`test_modfile.sh` compiles the source file and verifies that the correct
.mod files are generated.

Original-commit: flang-compiler/f18@a23f53c1a7d6f1dba157c1bc87ebc046d3b818e6
Reviewed-on: https://github.com/flang-compiler/f18/pull/126
Tree-same-pre-rewrite: false

[flang] Implement writing of .mod files.

Module file writing is implemented in mod-file.cc. They need to be
written after all semantic checking. Until then, for testing, write
them out whenever names are resolved.

There is a header comment in the .mod files but it is mostly a
placeholder until we can read them in and do something with it.

Rename `Symbol::details<D>` to `Symbol::get<D>`. This asserts that the
details of the symbol match D and returns that type. But we need a way
to access the details as a variant as well (not just one of its types).
`details()` is the best name for that, especially as we already have
`set_details()`. Renaming the old `details` to `get` also better matches
`has` which is used to check which variant is present.

Original-commit: flang-compiler/f18@8d14be1a1633ab2e8ee700a3709989769fbc1f14
Reviewed-on: https://github.com/flang-compiler/f18/pull/126
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#123 from flang-compiler/pmk1

Improve error recovery further, using a test case from Tim.

Original-commit: flang-compiler/f18@cd850a75df0c768bfe54a6ff54a59fe25f48c924
Reviewed-on: https://github.com/flang-compiler/f18/pull/123

[flang] Improve error recovery further, using a test case from Tim.

Original-commit: flang-compiler/f18@9ef79fa9913804168d151a5b15588dbfaa02957a
Reviewed-on: https://github.com/flang-compiler/f18/pull/123

[flang] Merge pull request flang-compiler/f18#122 from flang-compiler/pmk1

Fix two problems described in issue#121

Original-commit: flang-compiler/f18@4d8203ad354310de16a690fe83bfad3eb5c3ce68
Reviewed-on: https://github.com/flang-compiler/f18/pull/122

[flang] Extend documentation on extensions.

Original-commit: flang-compiler/f18@672e468252b221d53e5b87aad805b42820b2bfff
Reviewed-on: https://github.com/flang-compiler/f18/pull/122

[flang] Tweak code for readability and maybe better performance.

Original-commit: flang-compiler/f18@e4d9b8587e84714df3476f8f32ac156f36b32449
Reviewed-on: https://github.com/flang-compiler/f18/pull/122
Tree-same-pre-rewrite: false

[flang] More documentation.  These changes fix two bugs noted in f18 issue#121.

Original-commit: flang-compiler/f18@f386472c5ce6cf2f4f485c118213ae3fae6040e3
Reviewed-on: https://github.com/flang-compiler/f18/pull/122
Tree-same-pre-rewrite: false

[flang] Allow empty statements and improve error recovery error messages.

Original-commit: flang-compiler/f18@018e81e2c441ca54763e617a42457100c1291b42
Reviewed-on: https://github.com/flang-compiler/f18/pull/122
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#120 from flang-compiler/tsk1

Support intent-stmt and resolve subprogram prefixes and suffixes.

Original-commit: flang-compiler/f18@2206d453e1e7554f09ab01cfb5da8d48b5691cfd
Reviewed-on: https://github.com/flang-compiler/f18/pull/120

[flang] Sort enumerators in `enum class Attr`.

Original-commit: flang-compiler/f18@ce43e4e556e891e68d36377add88fecd13ab4f2e
Reviewed-on: https://github.com/flang-compiler/f18/pull/120

[flang] Support intent-stmt and resolve subprogram prefixes and suffixes.

Recognize `IntentStmt` and use `HandleAttributeStmt()` to implement it
as is done with other attribute statements. Add `Attr::INTENT_INOUT` as
a separate attribute for `INTENT(INOUT)`.

Collect attributes from the prefix and suffix of `FunctionStmt` and
`SubroutineStmt` (including `BIND(C)`) and set them on the subprogram
symbol.

Create a test for this using `test_symbol.sh`. It compiles with
`-funparse-with-symbols` and compares the output with the symbols in
comments in the input.

Change `test_errors.sh` to be similar to `test_symbol.sh`: check usage
and allow `F18` environment variable to override the path to the
compiler.

Original-commit: flang-compiler/f18@384828a22f53d828a3140640ca89f5819ada394d
Reviewed-on: https://github.com/flang-compiler/f18/pull/120
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#119 from flang-compiler/pmk1

Use braces in `auto` initializers in lib/{parser,common,evaluate}

Original-commit: flang-compiler/f18@1aeba0c214b3a6388de630345eb5164749be598d
Reviewed-on: https://github.com/flang-compiler/f18/pull/119

[flang] Documentation

Original-commit: flang-compiler/f18@d2855c6474b273987492f7f879c0f7a674f35c8f
Reviewed-on: https://github.com/flang-compiler/f18/pull/119

[flang] merge and reformat

Original-commit: flang-compiler/f18@2e3d67aa79e1e7e0af58e1d21bb500a987338c03
Reviewed-on: https://github.com/flang-compiler/f18/pull/119
Tree-same-pre-rewrite: false

[flang] correct typo in unparse.cc found in test

Original-commit: flang-compiler/f18@1aa60cccc4f0a56802551d2ecae8eba4f5ed668b
Reviewed-on: https://github.com/flang-compiler/f18/pull/119
Tree-same-pre-rewrite: false

[flang] Use braces for auto initialization in lib/common and lib/evaluate

Original-commit: flang-compiler/f18@b0d1dd434bbcd55613d2f0b67863905baa8f818b
Reviewed-on: https://github.com/flang-compiler/f18/pull/119
Tree-same-pre-rewrite: false

[flang] Use braces in auto initializers.

Original-commit: flang-compiler/f18@b68fdff537abc5402751d2f2842ff6d191f4d1fe
Reviewed-on: https://github.com/flang-compiler/f18/pull/119
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#118 from flang-compiler/pmk2

Better error recovery in the face of input that's not Fortran at all

Original-commit: flang-compiler/f18@7edf728444614f0eeda94c6b6dddd407a0cf380b
Reviewed-on: https://github.com/flang-compiler/f18/pull/118

[flang] Better error recovery (for a case from Tim) and fix a problem where context is lost.

Original-commit: flang-compiler/f18@522822fd5a44aee41998e25f0691e44cbaaa202c
Reviewed-on: https://github.com/flang-compiler/f18/pull/118

[flang] Merge pull request flang-compiler/f18#117 from flang-compiler/pmk1

Variables

Original-commit: flang-compiler/f18@d38c14ef24b2785534f1b79d885a444cb64e978a
Reviewed-on: https://github.com/flang-compiler/f18/pull/117

[flang] Extend documentation

Original-commit: flang-compiler/f18@ac375a00ba871cc11244c5e111b42e7807648a14
Reviewed-on: https://github.com/flang-compiler/f18/pull/117

[flang] Address review comments

Original-commit: flang-compiler/f18@9e59b9b79d690e0293c61a889da28cbd42ac5194
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] Resolve build issues with older compilers.

Original-commit: flang-compiler/f18@d8723284d3750e05fbf6290d99faecd5cd8a774e
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] Refine variable structure definitions, add references to Standard.

Original-commit: flang-compiler/f18@dbc6d45e02ded14d01ac856857e3e45b4cc0aa1a
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] Start cleaning up for merging.

Original-commit: flang-compiler/f18@7355bd5b4238a5fe57da8c1446a20bb0caf26fc7
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] Use Indirection.  Get variables to work in int expressions.

Original-commit: flang-compiler/f18@1000717da820d87b330719034281a69eaf37bb89
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] More abstraction in expressions.

Original-commit: flang-compiler/f18@2dc425acf58e9c4a836d6cb73b436b0059a5309f
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] tweaks

Original-commit: flang-compiler/f18@624c1d2ec8539ae96f00c99ca90c56a0d7e3d266
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] clean up dumping code

Original-commit: flang-compiler/f18@29698883601984a16c48e4b5b3a1b314930ad47a
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] Fix issue flang-compiler/f18#113.

Original-commit: flang-compiler/f18@835e51b6e6e4030a26398f4c0e550d7baad13aa9
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] work on variables and traversal

Original-commit: flang-compiler/f18@432779b2218c500a18dec7f1018270bf150be0cb
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] Commit work in progress to branch for f18 repository move.

Original-commit: flang-compiler/f18@e0db6903c74b5cadfff461da9f4e51b59e165ba0
Reviewed-on: https://github.com/flang-compiler/f18/pull/117
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#116 from flang-compiler/tsk8

Fix bug recognizing derived type constructor call

Original-commit: flang-compiler/f18@e52910514495abf55094defb6668447e178e1c84
Reviewed-on: https://github.com/flang-compiler/f18/pull/116

[flang] Fix bug recognizing derived type constructor call

A ProcedureDesignator is a derived type constructor call if the name
resolves to a derived type. We need to recognize it as such and not
report an error. It may be in another derived type so we have to call
FindSymbol() first to find the derived type.

Most of the diffs are due to `symbol` changing from a reference to a
pointer.

In this example we were reporting an error on the first `t1()` and
resolving the second as an external function call.
```
module m
  type :: t1
  end type
  type(t1) :: x = t1()
  type t2
    type(t1) :: y = t1()
  end type
end module
```

Original-commit: flang-compiler/f18@717b22ca2b9e7ade24454b90b980f8c825fe4b12
Reviewed-on: https://github.com/flang-compiler/f18/pull/116

[flang] Merge pull request flang-compiler/f18#114 from flang-compiler/tsk5

Check consistency of generic interfaces.

Original-commit: flang-compiler/f18@16ed60240ab8a81f5a64cad2741899b9b53fe44e
Reviewed-on: https://github.com/flang-compiler/f18/pull/114

[flang] Add missing copyright.

Original-commit: flang-compiler/f18@cf7087b3816a3cc5421bb75c4bccf358ac7d2db6
Reviewed-on: https://github.com/flang-compiler/f18/pull/114

[flang] Check consistency of generic interfaces.

The specific procedures in a generic interface must be all functions or
all subroutines. If there is a derived type with the same name they can
only be functions.

Original-commit: flang-compiler/f18@e02cef047a02585caba550da01dcf7f5e75942dd
Reviewed-on: https://github.com/flang-compiler/f18/pull/114
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#112 from ThePortlandGroup/tsk5

Support unparse with symbol annotations.

Original-commit: flang-compiler/f18@fcca042a10b3908ffb72d8cf7ae86c71cffdfc6d
Reviewed-on: https://github.com/flang-compiler/f18/pull/112

[flang] Add -funparse-with-symbols to enable new behavior

Original-commit: flang-compiler/f18@7ad44e7e33de7020a94378b8f98395e7d5edef51
Reviewed-on: https://github.com/flang-compiler/f18/pull/112

[flang] Support unparse with symbol annotations.

When `-fdebug-dump-symbols` is supplied with `-funparse`, include symbol
information in comments in the Fortran output. This will be used for
testing to verify that correct symbols are defined and references in
the right place.

In `UnparseWithSymbols()`, walk the parse tree and collect symbol
definitions and references, organized by statement. When a symbol is
defined across several statement it is associated with the first.
The definition of implicitly defined symbols is associated with the
first reference.

To write out the symbol information, a new optional argument is added to
`Unparse()`: it is a function that is called immediately before each
statement is unparsed. We pass in a function that prints out the symbol
information collected for that statement.

Add `Symbol::GetType()` to make it easier to write the symbol types
and add `Symbol::SetType()` for uniformity.

Original-commit: flang-compiler/f18@2e827de4ad23d036fa3436382c8a878a991f11f5
Reviewed-on: https://github.com/flang-compiler/f18/pull/112
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#111 from ThePortlandGroup/pmk-expr

Expressions

Original-commit: flang-compiler/f18@802e18cb5ae3dae3d5f8d2e3bce0807cd362660e
Reviewed-on: https://github.com/flang-compiler/f18/pull/111

[flang] Incorporate suggestions from code review.

Original-commit: flang-compiler/f18@c66bd9ab15846afcaed129764b8c958f277e071f
Reviewed-on: https://github.com/flang-compiler/f18/pull/111

[flang] Begin folding, with simple test, as sanity check on usability.

Original-commit: flang-compiler/f18@3839c65cd5ba3a7d2ab84bd48a371659a249b383
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] clean up for push

Original-commit: flang-compiler/f18@8b5bbcedba41828d24e01251b06789d3eef4ebf8
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Prepare for check-in

Original-commit: flang-compiler/f18@2f5b2d5f40106a61bee6b726d2d7915bb891fe85
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Operator overloads for expression construction.

Original-commit: flang-compiler/f18@a4d3a736cf3d0c90fd5e26fb25b3adbc4530179a
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] clean up clang warnings from master

Original-commit: flang-compiler/f18@1c9aa95f8ddb2bd2b8366f84bd4cf7144de4c279
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] More refinement, use const on subexpressions.

Original-commit: flang-compiler/f18@f484325c61fd5d7d4aec1fdbbf24fb54a97be907
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Simplification

Original-commit: flang-compiler/f18@a50ce6e499f484deeb1296dbb1139a9b8ca91b4a
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] fix builds, all now clear

Original-commit: flang-compiler/f18@7c32a531a0cfe6a766fe0c2faa2b7e26ee957a14
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Dump complex expressions

Original-commit: flang-compiler/f18@da25b870d32bebc2b3055ede771efaf6701e8a3f
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] More dumping code

Original-commit: flang-compiler/f18@43d147144a843956ab37ae4714902795c652e347
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Use unique_ptr for operands.  Refactor comparisons.

Original-commit: flang-compiler/f18@92e154e76eeac6ea91c62cdc0081fb35258f8c78
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Expression formatting

Original-commit: flang-compiler/f18@3d0977a57e32460ac0cf808a7e4b5bcbdb3d30ba
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Change memcpy to memmove for overlap case.

Original-commit: flang-compiler/f18@cb400284e48a486922ee4420f02448eb68966fcf
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Numeric constant formatting and tests.

Original-commit: flang-compiler/f18@ade64420201c45d8082c65ba21e6e7d161605300
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Character LEN, operator overloadings

Original-commit: flang-compiler/f18@08c32de24cae7ea9091f665337c1c2386ec87a32
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Finish first cut at expression.h.

Original-commit: flang-compiler/f18@07142e7fad2b8c672df7549caec8be0d1c0d3856
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Expression work

Original-commit: flang-compiler/f18@b60c84fff491d19402f95f825b4be42f239ac2a9
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] reformat c++

Original-commit: flang-compiler/f18@6c5c9b316542b558d1d4e3883c92e172f374e230
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] first cut at expressions

Original-commit: flang-compiler/f18@b06c5486e4d80e017a9c697c79ac588a88498547
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] begin expression representation

Original-commit: flang-compiler/f18@627c057d5c8392914eb186e8f6dacab40b5a6666
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Documentation

Original-commit: flang-compiler/f18@27f6927053fa685b9366647fa02b595ffd830441
Reviewed-on: https://github.com/flang-compiler/f18/pull/111
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#110 from ThePortlandGroup/tsk1

Fix problems in PR 109 when compiling with clang.

Original-commit: flang-compiler/f18@f21c334589e580c1c32aa3b8abad000636283e8f
Reviewed-on: https://github.com/flang-compiler/f18/pull/110

[flang] Fix problems in PR 109 when compiling with clang.

This gets the code base back to compiling cleanly with clang after
pull request 109.

There were two overloadings of `Post(const parser::DeclarationTypeSpec::Type &)`.
The one in DeclarationVisitor needed to call the one in DeclTypeSpecVisitor.
This was fixed by introducing a new function, SetDerivedDeclTypeSpec, to do
the equivalent thing.

Original-commit: flang-compiler/f18@81e447bf4ec076f8fa823c0c61c9dd72e1f62fe4
Reviewed-on: https://github.com/flang-compiler/f18/pull/110

[flang] Merge pull request flang-compiler/f18#109 from ThePortlandGroup/tsk5

Name resolution for derived types.

Original-commit: flang-compiler/f18@5317d4f30ae926ee4f839d3afab68363d1d9c5c9
Reviewed-on: https://github.com/flang-compiler/f18/pull/109

[flang] Name resolution for derived types.

This consists of:
- a new kind of symbols to represent them with DerivedTypeDetails
- creating symbols for derived types when they are declared
- creating a new kind of scope for the type to hold component symbols
- resolving entity declarations of objects of derived type
- resolving references to objects of derived type and to components
- handling derived types with same name as generic

Type parameters are not yet implemented.

Refactor DeclTypeSpec to be a value class wrapping an IntrinsicTypeSpec
or a DerivedTypeSpec (or neither in the TypeStar and ClassStar cases).
Store DerivedTypeSpec objects in a new structure the current scope
MakeDerivedTypeSpec so that DeclTypeSpec can just contain a pointer to
them, as it currently does for intrinsic types.

In GenericDetails, add derivedType field to handle case where generic
and derived type have the same name. The generic is in the scope and the
derived type is referenced from the generic, similar to the case where a
generic and specific have the same name. When one of these names is
mis-recognized, we sometimes have to fix up the 'occurrences' lists
of the symbols.

Assign implicit types as soon as an entity is encountered that requires
one. Otherwise implicit derived types won't work. When we see 'x%y' we
have to know the type of x in order to resolve y. Add an Implicit flag
to mark symbols that were implicitly typed

For symbols that introduce a new scope, include a pointer back to that
scope.

Add CurrNonTypeScope() for the times when we want the current scope but
ignoring derived type scopes. For example, that happens when looking for
types or parameters, or creating implicit symbols.

Original-commit: flang-compiler/f18@9bd16da020b64b78ed3928e0244765cd2e2d8068
Reviewed-on: https://github.com/flang-compiler/f18/pull/109

[flang] Refactor DeclTypeSpec and DerivedTypeSpec classes.

Make DerivedTypeSpec a simple wrapper around the name of the type.
Leave out type parameter values until we are ready to resolve them
as well.

Change DeclTypeSpec to be an old-fashioned union with an enum to
indicate what is in it. std::variant doesn't work well here because
we wanted the enum visible in the class' API and there is not a
1-to-1 mapping between enumerators and data stored.

Original-commit: flang-compiler/f18@03bdeef790375ea7dbac6abf1118ec743c55a1b6
Reviewed-on: https://github.com/flang-compiler/f18/pull/109
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#107 from ThePortlandGroup/tsk2

Change how memory for Symbol instances is managed.

Original-commit: flang-compiler/f18@ccf6aeac622038c5d2a3151d4566aa2536e9aea2
Reviewed-on: https://github.com/flang-compiler/f18/pull/107

[flang] Change how memory for Symbol instances is managed.

With this change, all instances Symbol are stored in class Symbols.
Scope.symbols_, which used to own the symbol memory, now maps names to
Symbol* instead. This causes a bunch of reference-to-pointer changes
because of the change in type of key-value pairs. It also requires a
default constructor for Symbol, which means owner_ can't be a reference.

Symbols manages Symbol instances by allocating a block of them at a time
and returning the next one when needed. They are never freed.

The reason for the change is that there are a few cases where we need
to have a two symbols with the same name, so they can't both live in
the map in Scope. Those are:
1. When there is an erroneous redeclaration of a name we may delete the
   first symbol and replace it with a new one. If we have saved a pointer
   to the first one it is now dangling. This can be seen by running
   `f18 -fdebug-dump-symbols -fparse-only test/semantics/resolve19.f90`
   under valgrind. Subroutine s is declared twice: each results in a
   scope that contains a pointer back to the symbol for the subroutine.
   After the second symbol for s is created the first is gone so the
   pointer in the scope is invalid.
2. A generic and one of its specifics can have the same name. We currently
   handle that by moving the symbol for the specific into a unique_ptr
   in the generic. So in that case the symbol is owned by another symbol
   instead of by the scope. It is simpler if we only have to deal with
   moving the raw pointer around.
3. A generic and a derived type can have the same name. This case isn't
   handled yet, but it can be done like flang-compiler/f18#2 above. It's more complicated
   because the derived type and the generic can be declared in either
   order.

Original-commit: flang-compiler/f18@55a68cf0235c8a3ac855de7dc0e2b08690866be0
Reviewed-on: https://github.com/flang-compiler/f18/pull/107

[flang] Fix bug in adding symbols to parse tree.

We were collecting symbols in a map of SourceName to Symbol*.
This is wrong because sometimes different occurrences of a name
map to different symbols (e.g. in different scopes).
SourceName::begin() is unique for each occurrence so use that
as the map key instead.

The problem can be reproduced by running:
`f18 -fdebug-resolve-names -fparse-only -fdebug-dump-parse-tree`
on the following source. The two symbols 'i' should have different
types and they were both coming out as INTEGER because they both
pointed to the first symbol for 'i'.

```
module m
  integer :: i
contains
  subroutine s
    real :: i
  end
end
```

Original-commit: flang-compiler/f18@a165c717ff20d3ccca334b91fa538f54b54071cf
Reviewed-on: https://github.com/flang-compiler/f18/pull/107
Tree-same-pre-rewrite: false

[flang] Merge pull request flang-compiler/f18#106 from ThePortlandGroup/pmk-value

Rearrange some facilities into a new lib/common.

Original-commit: flang-compiler/f18@12477c3c3090b6cd2db0fa247aab073808a94511
Reviewed-on: https://github.com/flang-compiler/f18/pull/106

[flang] Rearrange some facilities into a new lib/common.

Original-commit: flang-compiler/f18@279af1e817b1266dd57689e462272f8e29496798
Reviewed-on: https://github.com/flang-compiler/f18/pull/106

[flang] Merge pull request flang-compiler/f18#105 from ThePortlandGroup/tsk2

Add name resolution tests

Original-commit: flang-compiler/f18@edf182d458cb5a362369fb0b71a3e98282439559
Reviewed-on: https://github.com/flang-compiler/f18/pull/105

[flang] Add name resolution tests

The Fortran source files in test/semantics all contain expected
errors in comments. The script test_errors.sh compiles a file with
'f18 -fdebug-resolve-names -fparse-only' and compares the actual
errors produced against the expected ones.

The change to resolve15.f90 is necessary because test_errors.sh can't
handle two expected errors for the same source line.

A useful command to run these is 'ctest -R f90 --output-on-failure'.
-R means only run tests with f90 in the name
--output-on-failure prints the output of test_errors.sh when a test
fails, showing the expected and actual messages that differ.

Original-commit: flang-compiler/f18@df18ee7bc95628503b37648d98c5ae25bc74b227
Reviewed-on: https://github.com/flang-compiler/f18/pull/105

[flang] Merge pull request flang-compiler/f18#101 from ThePortlandGroup/pmk-evaluate

Basic operation evaluation framework

Original-commit: flang-compiler/f18@e91fac085d347639d1ddc5e6baf8d9b6fc41f3f3
Reviewed-on: https://github.com/flang-compiler/f18/pull/101

[flang] Test 64-bit reals too.

Original-commit: flang-compiler/f18@67fd5514417b2c920be85e0919bf06b06a399e3c
Reviewed-on: https://github.com/flang-compiler/f18/pull/101

[flang] Address review comments

Original-commit: flang-compiler/f18@d96917c70130b12462d28189ded5e6243e8c854e
Reviewed-on: https://github.com/flang-compiler/f18/pull/101
Tree-same-pre-rewrite: false

[flang] More rearrangement, and debug an edge case with Underflow flag.

Original-commit: flang-compiler/f18@57ef08433ebc1b174551dfaca0c57ba97a1d7806
Reviewed-on: https://github.com/flang-compiler/f18/pull/101
Tree-same-pre-rewrite: false

[flang] Move member functions complex.h -> complex.cc

Original-commit: flang-compiler/f18@445333b13e212816f42b38c940b89e6a90708414
Reviewed-on: https://github.com/flang-compiler/f18/pull/101
Tree-same-pre-rewrite: false

[flang] Remove work-around in resolve-names.cc.

Original-commit: flang-compiler/f18@5dc0e037f59f6e58d45d7f65ec52e7cd5525b78c
Reviewed-on: https://github.com/flang-compiler/f18/pull/101
Tree-same-pre-rewrite: false