Commit Graph

2201 Commits

Author SHA1 Message Date
Felix Berger 0ec812023b [clang-tidy] performance-unnecessary-copy-initialization: Do not remove comments on new lines.
When deleting the copy assignment statement because copied variable is not used
only remove trailing comments on the same line.

Differential Revision: https://reviews.llvm.org/D105734

Reviewed-by: ymandel
2021-07-12 16:23:04 -04:00
Felix Berger 187e050b33 [clang-tidy] performance-unnecessary-copy-initialization: Disable structured bindings.
Structured bindings can currently trigger the check and lead to a wrong
fix. Because the DecompositionDecl itself is not used and the check does not
iterate through its the decl's bindings to verify whether the bindings' holding
vars are used this leads to the whole statement to be deleted.

To support structured bindings properly 3 cases would need to be considered.

  1. All holding vars are not used -> The statement can be deleted.
  2. All holding vars are used as const or not used -> auto can be converted to const auto&.
  3. Neither case is true -> leave unchanged.

In the check we'll have to separate the logic that determines this from the code
that produces the diagnostic and fixes and first determine which of the cases
we're dealing with before creating fixes.

Since this is a bigger refactoring we'll disable structured bindings for now to
prevent incorrect fixes.

Differential Revision: https://reviews.llvm.org/D105727

Reviewed-by: ymandel
2021-07-12 09:55:27 -04:00
Whisperity 0fba450b97 [clang-tidy] Suppress reports to patternedly named parameters in 'bugprone-easily-swappable-parameters'
While the original check's purpose is to identify potentially dangerous
functions based on the parameter types (as identifier names do not mean
anything when it comes to the language rules), unfortunately, such a plain
interface check rule can be incredibly noisy. While the previous
"filtering heuristic" is able to find many similar usages, there is an entire
class of parameters that should not be warned about very easily mixed by that
check: parameters that have a name and their name follows a pattern,
e.g. `text1, text2, text3, ...`.`

This patch implements a simple, but powerful rule, that allows us to detect
such cases and ensure that no warnings are emitted for parameter sequences that
follow a pattern, even if their types allow for them to be potentially mixed at a call site.

Given a threshold `k`, warnings about two parameters are filtered from the
result set if the names of the parameters are either prefixes or suffixes of
each other, with at most k letters difference on the non-common end.
(Assuming that the names themselves are at least `k` long.)

 - The above `text1, text2` is an example of this. (Live finding from Xerces.)
 - `LHS` and `RHS` are also fitting the bill here. (Live finding from... virtually any project.)
 - So does `Qmat, Tmat, Rmat`. (Live finding from I think OpenCV.)

Reviewed By: aaron.ballman

Differential Revision: http://reviews.llvm.org/D97297
2021-06-28 10:49:37 +02:00
Whisperity b9ece03461 [clang-tidy] Suppress reports to similarly used parameters in 'bugprone-easily-swappable-parameters'
There are several types of functions and various reasons why some
"swappable parameters" cannot be fixed with changing the parameters' types, etc.
The most common example might be int `min(int a, int b)`... no matter what you
do, the two parameters must remain the same type.

The **filtering heuristic** implemented in this patch deals with trying to find
such functions during the modelling and building of the swappable parameter
range.
If the parameter currently scrutinised matches either of the predicates below,
it will be regarded as **not swappable** even if the type of the parameter
matches.

Reviewed By: aaron.ballman

Differential Revision: http://reviews.llvm.org/D78652
2021-06-28 10:49:37 +02:00
Whisperity e33d047883 [clang-tidy] Extend 'bugprone-easily-swappable-parameters' with mixability because of implicit conversions
Adds a relaxation option ModelImplicitConversions which will make the check
report for cases where parameters refer to types that are implicitly
convertible to one another.

Example:

    struct IntBox { IntBox(int); operator int(); };
    void foo(int i, double d, IntBox ib) {}

Implicit conversions are the last to model in the set of things that are
reasons for the possibility of a function being called the wrong way which is
not always immediately apparent when looking at the function (signature or
call).

Reviewed By: aaron.ballman, martong

Differential Revision: http://reviews.llvm.org/D75041
2021-06-28 10:49:37 +02:00
Whisperity 961e9e6af6 [clang-tidy] Extend 'bugprone-easily-swappable-parameters' with optionally considering differently qualified types mixable
Adds a relaxation option QualifiersMix which will make the check report for
cases where parameters refer to the same type if they only differ in qualifiers.

This makes cases, such as the following, not warned about by default, produce
a warning.

    void* memcpy(void* dst, const void* src, unsigned size) {}

However, unless people meticulously const their local variables, unfortunately,
even such a function carry a potential swap:

    T* obj = new T; // Not const!!!
    void* buf = malloc(sizeof(T));

    memcpy(obj, buf, sizeof(T));
    //     ^~~  ^~~ accidental swap here, even though the interface "specified" a const.

Reviewed By: aaron.ballman

Differential Revision: http://reviews.llvm.org/D96355
2021-06-28 10:49:37 +02:00
Whisperity 26d864b44b [clang-tidy] Extend 'bugprone-easily-swappable-parameters' with `typedef` and `const &` diagnostics
The base patch only deals with strict (canonical) type equality, which is
merely a subset of all the dangerous function interfaces that we intend to
find.
In addition, in the base patch, canonical type equivalence is not diagnosed in
a way that is immediately apparent to the user.

This patch extends the check with two features:

 * Proper typedef diagnostics and explanations to the user.
 * "Reference bind power" matching.

Case 2 is a necessary addition because in every case someone encounters a
function `f(T t, const T& tr)`, any expression that might be passed to either
can be passed to both. Thus, such adjacent parameter sequences should be
matched.

Reviewed By: aaron.ballman

Differential Revision: http://reviews.llvm.org/D95736
2021-06-28 10:49:37 +02:00
Whisperity 499e39c598 [clang-tidy] Add 'bugprone-easily-swappable-parameters' check
Finds function definitions where parameters of convertible types follow
each other directly, making call sites prone to calling the function
with swapped (or badly ordered) arguments.

Such constructs are usually the result of inefficient design and lack of
exploitation of strong type capabilities that are possible in the
language.

This check finds and flags **function definitions** and **not** call
sites!

Reviewed By: aaron.ballman, alexfh

Differential Revision: http://reviews.llvm.org/D69560
2021-06-28 10:49:37 +02:00
Felix Berger bdd5da9dec [clang-tidy] performance-unnecessary-copy-initialization: Directly examine the initializing var's initializer.
This fixes false positive cases where a reference is initialized outside of a
block statement and then its initializing variable is modified. Another case is
when the looped over container is modified.

Differential Revision: https://reviews.llvm.org/D103021

Reviewed-by: ymandel
2021-06-18 15:25:17 -04:00
Haojian Wu 1a53fb0596 [clang-tidy] NarrowingConversionsCheck should support inhibiting conversions of
mixed integer and floating point types with WarnOnEquivalentBitWidth=0.

Also standardize control flow of handleX conversion functions to make it easier to be consistent.

Patch by Stephen Concannon!

Differential Revision: https://reviews.llvm.org/D103894
2021-06-11 13:02:48 +02:00
Ivan Murashko 47d138c939 [clang-tidy] LIT test fix for Remark diagnostic
There is a followup fix for a unit test introduced at D102906. The test file was placed into a temp folder and test assumed that it would be visible without the full path specification.

This behaviour can be changed in future and it would be good to specify full path to the file at the test.

Test Plan:
```
ninja check-clang-tools
```

Reviewed By: DmitryPolukhin

Differential Revision: https://reviews.llvm.org/D104021
2021-06-11 02:02:36 -07:00
Guillaume Chatelet 89c41c335d [clang-tidy] Allow disabling integer narrowing conversions for cppcoreguidelines-narrowing-conversions
Differential Revision: https://reviews.llvm.org/D104018
2021-06-10 12:41:57 +00:00
Felix Berger efa4dbc32c [clang-tidy] performance-unnecessary-copy-initialization: Look at the canonical type when checking for aliases.
This fixes a false positive case where for instance a pointer is obtained and declared using `auto`.

Differential Revision: https://reviews.llvm.org/D103018

Reviewed-by: ymandel
2021-06-09 16:36:53 -04:00
Felix Berger 5dbe3bf4b8 [clang-tidy] performance-unnecessary-copy-initialization: Remove the complete statement when the copied variable is unused.
It is not useful to keep the statement around and can lead to compiler
warnings when -Wall (-Wunused-variable specifically) turned on.

Differential Revision: https://reviews.llvm.org/D102175

Reviewed-by: ymandel
2021-06-09 15:52:48 -04:00
Ivan Murashko 7f2f0247f8 Remark was added to clang tooling Diagnostic
The diff adds Remark to Diagnostic::Level for clang tooling. That makes
Remark diagnostic level ready to use in clang-tidy checks: the
clang-diagnostic-module-import becomes visible as a part of the change.
2021-05-24 11:21:44 -04:00
Haojian Wu 9f36306cc9 [clang-tidy] Fix a crash on invalid code for memset-usage check.
Differential Revision: https://reviews.llvm.org/D102714
2021-05-19 09:53:18 +02:00
Georgy Komarov ab92a4c26f
[clang-tidy] Fix altera-struct-pack-align crash for struct fields with incomplete type
We can only use ASTContext::getTypeInfo for complete types.

This fixes bugzilla issue 50313.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D102569
2021-05-17 16:50:47 +03:00
Artem Dergachev 5ad2eeeada [clang-tidy] bugprone-infinite-loop: React to ObjC ivars and messages.
If the loop condition is a value of an instance variable, a property value,
or a message result value, it's a good indication that the loop is not infinite
and we have a really hard time proving the opposite so suppress the warning.

Differential Revision: https://reviews.llvm.org/D102294
2021-05-13 11:25:02 -07:00
Artem Dergachev 46c6c08c94 [clang-tidy] bugprone-infinite-loop: forFunction() -> forCallable().
Take advantage of the new ASTMatcher added in D102213 to fix massive false negatives of the infinite loop checker on Objective-C.

Differential Revision: https://reviews.llvm.org/D102214
2021-05-13 11:25:01 -07:00
Georgy Komarov e07753c881
[clang-tidy] Fix test that requires Windows platofrm
This commit fixes the cppcoreguidelines-pro-type-vararg test when it
runs on a Windows host, but the toolchain is targeted a non-Windows
platform.

Reviewed By: njames93

Differential Revision: https://reviews.llvm.org/D102337
2021-05-13 15:51:53 +03:00
Stephen Concannon 211761332e [clang-tidy] Allow opt-in or out of some commonly occuring patterns in NarrowingConversionsCheck.
Within clang-tidy's NarrowingConversionsCheck.
* Allow opt-out of some common occurring patterns, such as:
  - Implicit casts between types of equivalent bit widths.
  - Implicit casts occurring from the return of a ::size() method.
  - Implicit casts on size_type and difference_type.
* Allow opt-in of errors within template instantiations.

This will help projects adopt these guidelines iteratively.
Developed in conjunction with Yitzhak Mandelbaum (ymandel).

Patch by Stephen Concannon!

Differential Revision: https://reviews.llvm.org/D99543
2021-05-12 20:51:25 +02:00
Hana Joo 163325086c
[clang-tidy] Enable the use of IgnoreArray flag in pro-type-member-init rule
The `IgnoreArray` flag was not used before while running the rule. Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=47288 | b/47288 ]]

Reviewed By: njames93

Differential Revision: https://reviews.llvm.org/D101239
2021-05-12 12:57:21 +01:00
Artem Dergachev 91ca3269a1 [clang-tidy] Aliasing: Add support for aggregates with references.
When a variable is used in an initializer of an aggregate
for its reference-type field this counts as aliasing.

Differential Revision: https://reviews.llvm.org/D101791
2021-05-10 14:00:31 -07:00
Artem Dergachev 9b292e0edc [clang-tidy] Aliasing: Add more support for captures.
D96215 takes care of the situation where the variable is captured into
a nearby lambda. This patch takes care of the situation where
the current function is the lambda and the variable is one of its captures
from an enclosing scope.

The analogous problem for ^{blocks} is already handled automagically
by D96215.

Differential Revision: https://reviews.llvm.org/D101787
2021-05-10 14:00:30 -07:00
Artem Dergachev 43f4331edf [clang-tidy] Aliasing: Add support for captures.
The utility function clang::tidy::utils::hasPtrOrReferenceInFunc() scans the
function for pointer/reference aliases to a given variable. It currently scans
for operator & over that variable and for declarations of references to that
variable.

This patch makes it also scan for C++ lambda captures by reference
and for Objective-C block captures.

Differential Revision: https://reviews.llvm.org/D96215
2021-05-10 14:00:30 -07:00
Frank Derry Wanye 83af66e18e new altera ID dependent backward branch check
This lint check is a part of the FLOCL (FPGA Linters for OpenCL) project
out of the Synergy Lab at Virginia Tech.

FLOCL is a set of lint checks aimed at FPGA developers who write code
in OpenCL.

The altera ID dependent backward branch lint check finds ID dependent
variables and fields used within loops, and warns of their usage. Using
these variables in loops can lead to performance degradation.
2021-05-06 17:01:39 -04:00
Nathan James e1c729c568
[clang-tidy][NFC] Update tests and Default options to use boolean value
Change instances where options which are boolean are assigned the value 1|0 to use true|false instead.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D101721
2021-05-04 18:17:56 +01:00
Georgy Komarov c2e9baf2e8
[clang-tidy] Fix cppcoreguidelines-pro-type-vararg false positives with __builtin_ms_va_list
This commit fixes cppcoreguidelines-pro-type-vararg false positives on
'char *' variables.

The incorrect warnings generated by clang-tidy can be illustrated with
the following minimal example:

```
goid foo(char* in) {
  char *tmp = in;
}
```

The problem is that __builtin_ms_va_list desugared as 'char *', which
leads to false positives.

Fixes bugzilla issue 48042.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D101259
2021-05-04 13:49:20 +03:00
Chris Hamilton cae3b70ceb [PR49761] Fix variadic arg handling in matcher
Mishandling of variadic arguments in a function call caused a crash
(runtime assert fail) in bugprone-infinite-loop tidy checker.  Fix
is to limit argument matching to the lesser of the number of variadic
params in the prototype or the number of actual args in the call.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D101108
2021-04-23 12:07:14 -05:00
Georgy Komarov 9a930aa5bd
[clang-tidy] Avoid bugprone-macro-parentheses warnings after goto argument
clang-tidy should not generate warnings for the goto argument without
parentheses, because it would be a syntax error.

The only valid case where an argument can be enclosed in parentheses is
"Labels as Values" gcc extension: https://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html.
This commit adds support for the label-as-values extension as implemented in clang.

Fixes bugzilla issue 49634.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D99924
2021-04-22 10:14:10 +03:00
Balázs Kéri bda20282cb [clang-tidy] Add exception flag to bugprone-unhandled-exception-at-new test. 2021-04-14 10:01:05 +02:00
Balázs Kéri 530456caf9 [clang-tidy] Add new check 'bugprone-unhandled-exception-at-new'.
Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D97196
2021-04-14 09:33:11 +02:00
Roman Lebedev 46b8ea2fff
[clang-tidy] Add check for implicit widening of multiplication result
Overflows are never fun.
In most cases (in most of the code), they are rare,
because usually you e.g. don't have as many elements.

However, it's exceptionally easy to fall into this pitfail
in code that deals with images, because, assuming 4-channel 32-bit FP data,
you need *just* ~269 megapixel image to case an overflow
when computing at least the total byte count.

In [[ https://github.com/darktable-org/darktable | darktable ]], there is a *long*, painful history of dealing with such bugs:
* https://github.com/darktable-org/darktable/pull/7740
* https://github.com/darktable-org/darktable/pull/7419
* eea1989f2c
* 70626dd95b
* https://github.com/darktable-org/darktable/pull/670
* 38c69fb1b2

and yet they clearly keep resurfacing still.

It would be immensely helpful to have a diagnostic for those patterns,
which is what this change proposes.

Currently, i only diagnose the most obvious case, where multiplication
is directly widened with no other expressions inbetween,
(i.e. `long r = (int)a * (int)b` but not even e.g. `long r = ((int)a * (int)b)`)
however that might be worth relaxing later.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D93822
2021-04-13 21:41:22 +03:00
Nathan James 27dfcd978e
[clang-tidy] Add <utility> include to misc-uniqueptr-reset-release
This is the only remaining check that creates `std::move` includes but doesn't add a `<utility>` include.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D97683
2021-04-12 23:32:15 +01:00
Jens Massberg 8a944d82cd [clang-tidy] Add option to ignore macros in readability-function-cognitive-complexity check.
(this was originally part of https://reviews.llvm.org/D96281 and has been split off into its own patch)

If a macro is used within a function, the code inside the macro
doesn't make the code less readable. Instead, for a reader a macro is
more like a function that is called. Thus the code inside a macro
shouldn't increase the complexity of the function in which it is called.
Thus the flag 'IgnoreMacros' is added. If set to 'true' code inside
macros isn't considered during analysis.

This isn't perfect, as now the code of a macro isn't considered at all,
even if it has a high cognitive complexity itself. It might be better if
a macro is considered in the analysis like a function and gets its own
cognitive complexity. Implementing such an analysis seems to be very
complex (if possible at all with the given AST), so we give the user the
option to either ignore macros completely or to let the expanded code
count to the calling function's complexity.

See the code example from vgeof (originally added as note in https://reviews.llvm.org/D96281)

   bool doStuff(myClass* objectPtr){
         if(objectPtr == nullptr){
             LOG_WARNING("empty object");
             return false;
         }
         if(objectPtr->getAttribute() == nullptr){
             LOG_WARNING("empty object");
             return false;
         }
         use(objectPtr->getAttribute());
     }

The LOG_WARNING macro itself might have a high complexity, but it do not make the
the function more complex to understand like e.g. a 'printf'.

By default 'IgnoreMacros' is set to 'false', which is the original behavior of the check.

Reviewed By: lebedev.ri, alexfh

Differential Revision: https://reviews.llvm.org/D98070
2021-04-12 18:46:12 +02:00
Whisperity 8fa3975247 [libtooling][clang-tidy] Fix off-by-one rendering issue with SourceRanges
There was an off-by-one issue with calculating the *exact* end location
of token ranges (as given by SomeDecl->getSourceRange()) which resulted in:

  xxx(something)
      ^~~~~~~~   // Note the missing ~ under the last character.

In addition, a test is added to keep the behaviour in check in the future.

This patch hotfixes commit 3b677b81ce.
2021-04-10 18:52:55 +02:00
Whisperity 3b677b81ce [libtooling][clang-tidy] Fix diagnostics not highlighting fed SourceRanges
Fixes bug http://bugs.llvm.org/show_bug.cgi?id=49000.

This patch allows Clang-Tidy checks to do

    diag(X->getLocation(), "text") << Y->getSourceRange();

and get the highlight of `Y` as expected:

    warning: text [blah-blah]
        xxx(something)
        ^   ~~~~~~~~~

Reviewed-By: aaron.ballman, njames93

Differential Revision: http://reviews.llvm.org/D98635
2021-04-10 16:43:44 +02:00
Felix Berger ddebed8e97 [clang-tidy] performance-* checks: Match AllowedTypes against qualified type names when they contain "::".
This allows users to be more precise and exclude a type in a specific namespace
from triggering the check instead of excluding all types with the same
unqualified name.

This change should not interfere with correctly configured clang-tidy setups
since an AllowedType with "::" would never match.

Differential Revision: https://reviews.llvm.org/D98738

Reviewed-by: ymandel, hokein
2021-04-06 15:41:35 -04:00
Alexander Lanin 0becc4d721 fix readability-braces-around-statements Stmt type dependency
Replaces Token based approach to identify EndLoc of Stmt with AST traversal.
This also improves handling of macros.

Fixes Bugs 22785, 25970 and 35754.
2021-03-25 09:44:41 -04:00
Dmitry Polukhin 338d162755 [clang-tidy] Ignore all spaces in the list of checks
This diff patch fixes issue with new line character after check name and before comma. Also ignores all other types of spaces like TAB.

Test Plan: ninja check-clang-tools

Differential Revision: https://reviews.llvm.org/D99180
2021-03-24 06:43:13 -07:00
Frank Derry Wanye 5a87f81fe9 new altera unroll loops check
This lint check is a part of the FLOCL (FPGA Linters for OpenCL)
project out of the Synergy Lab at Virginia Tech.

FLOCL is a set of lint checks aimed at FPGA developers who write code
in OpenCL.

The altera unroll loops check finds inner loops that have not been
unrolled, as well as fully-unrolled loops that should be partially
unrolled due to unknown loop bounds or a large number of loop
iterations.

Based on the Altera SDK for OpenCL: Best Practices Guide.
2021-03-22 13:09:53 -04:00
Nathan James 4dd92d61db
[clang-tidy] Fix bugprone-terminating-continue when continue appears inside a switch
Don't emit a warning if the `continue` appears in a switch context as changing it to `break` will break out of the switch rather than a do loop containing the switch.
Fixes https://llvm.org/PR49492.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D98338
2021-03-20 10:59:37 +00:00
Nathan James 9a5af541ee
[clang-tidy] Remove readability-deleted-default
The deprecation notice was cherrypicked to the release branch in f8b3298924 so its safe to remove this for the 13.X release cycle.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D98612
2021-03-16 14:03:33 +00:00
Dmitry Polukhin da55af7f1d [clang-tidy] Enable modernize-concat-nested-namespaces also on headers
For some reason the initial implementation of the check had an explicit check
for the main file to avoid being applied in headers. This diff removes this
check and add a test for the check on a header.

Similar approach was proposed in D61989 but review there got stuck.

Test Plan: added new test case

Differential Revision: https://reviews.llvm.org/D97563
2021-03-15 07:32:45 -07:00
Nathan James 0333dde923
[clang-tidy] Fix readability-identifer-naming duplicating prefix or suffix for replacements.
If a identifier has a correct prefix/suffix but a bad case, the fix won't strip them when computing the correct case, leading to duplication when the are added back.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D98521
2021-03-15 14:20:48 +00:00
Fangrui Song 46bf25a7c5 [test] Update tests 2021-03-09 22:32:28 -08:00
Martin Boehme e67d91faec [clang-tidy] Use-after-move: Ignore moves inside a try_emplace.
We have no way to reason about the bool returned by try_emplace, so we
simply ignore any std::move()s that happen in a try_emplace argument.
A lot of the time in this situation, the code will be checking the
bool and doing something else if it turns out the value wasn't moved
into the map, and this has been causing false positives so far.

I don't currently have any intentions of handling "maybe move" functions
more generally.

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D98034
2021-03-05 15:05:09 +01:00
Jens Massberg bff7faea20 [clang-tidy] Add options to describe individual core increments to readability-function-cognitive-complexity check.
Often you are only interested in the overall cognitive complexity of a
function and not every individual increment. Thus the flag
'DescribeBasicIncrements' is added. If it is set to 'true', each increment
is flagged. Otherwise, only the complexity of function with complexity
of at least the threshold are flagged.

By default 'DescribeBasisIncrements' is set to 'true', which is the original behavior of the check.

Added a new test for different flag combinations.

(The option to ignore macros which was original part of this patch will be added in another path)

Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D96281
2021-03-04 21:02:27 +01:00
Nathan James a85eb11129
[clang-tidy] Extend LoopConvert on array with `!=` comparison
Enables transforming loops of the form:
```
for (int i = 0; I != container.size(); ++I) { container[I]...; }
for (int i = 0; I != N; ++I) { FixedArrSizeN[I]...; }
```

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D97940
2021-03-04 18:58:59 +00:00
Felix Berger a189b3b9e8 [clang-tidy] performance-for-range-copy: Don't trigger on implicit type conversions.
This disables the check for false positive cases where implicit type conversion
through either an implicit single argument constructor or a member conversion
operator is triggered when constructing the loop variable.

Fix the test cases that meant to cover these cases.

Differential Revision: https://reviews.llvm.org/D97577

Reviewed-by: hokein
2021-03-02 20:02:48 -05:00