lint: warn about function definitions without header declaration

The existing warning was only issued for function declarations, not for
function definitions.

The interesting change in the tests is in msg_351.c. Many other tests
use non-static functions due to their syntactic brevity. In these
tests, the warning is disabled individually, to allow new functions to
be added without generating warning 351.

lint: add quotes around placeholders for the remaining messages

Reword some of the messages slightly, exchanging brevity for clarity.

Message 138 is kept as-is, as it is not yet covered by any tests.

Message 240 is kep as-is, as it is unreachable.

lint: in C99 mode, make implicit function declarations an error

In tree.c 1.294 from 2021-06-28, I had already tried this, but at that
time, there were too many implicit function definitions in the NetBSD
tree. Most of them were GCC builtins, which lint did not recognize.
Therefore I had to revert to a warning in tree.c 1.302 from 2021-06-30.

In the meantime, lint has learnt to recognize compiler builtins, see
is_compiler_builtin, so try again now. The build logs from x86_64,
i386, sparc and sparc64 show no more implicit function declarations.

lint: add __sync_ and _mm_ as prefixes for builtin functions

These two additions cover all cases that occur in the current NetBSD
build on x86_64. This allows build_name to use the usual pattern 'if
Sflag then error else if sflag then warning'. That function currently
issues a warning in C99 as well, even though C99 prohibits implicit
function declarations.

lint: do not warn about use of implicitly declared GCC builtins

lint: in C99 mode, only warn about implicit function declarations

Since tree.c 1.294 from 2021-06-28 (two days ago), lint errored out on
an implicit function declaration. In principle it is correct to do so
since C99 requires it, but in practice there are a several functions
that are not declared in the translation unit itself since they are
provided by the compiler. Typical examples for GCC and Clang are the
various functions named '__builtin_*' and '__atomic_*'.

For now, only warn about these but don't error out.

lint: mention the name of an implicitly declared function

In the regular NetBSD builds, this happened in swab.c:65. That line
contains __predict_false, which may or may not be a macro. In other
cases, there may be more than one function call in a single line.

tests/lint: extend test for message 215 about implicit function

lint: fix type name in message 101 for wrong member name

tests/lint: extend and explain test for implicit function declaration

lint: in C99 mode, complain about implicitly declared functions

C99, foreword, p5, item 22 lists among the major changes from C90:
"remove implicit function declaration".

lint: force each test to declare the expected diagnostics

By listing the expected diagnostics directly at the code that triggers
the diagnostics, it is easier to cross-check whether the diagnostics
make sense.

No functional change to lint itself.

lint: add a test for each message produced by lint1

Having a test for each message ensures that upcoming refactorings don't
break the basic functionality. Adding the tests will also discover
previously unknown bugs in lint.

The tests ensure that every lint message can actually be triggered, and
they demonstrate how to do so. Having a separate file for each test
leaves enough space for documenting historical anecdotes, rationale or
edge cases, keeping them away from the source code.

The interesting details of this commit are in Makefile and
t_integration.sh. All other files are just auto-generated.

When running the tests as part of ATF, they are packed together as a
single test case. Conceptually, it would have been better to have each
test as a separate test case, but ATF quickly becomes very slow as soon
as a test program defines too many test cases, and 50 is already too
many. The time complexity is O(n^2), not O(n) as one would expect.
It's the same problem as in tests/usr.bin/make, which has over 300 test
cases as well.

lint: add quotes around placeholders for the remaining messages

Reword some of the messages slightly, exchanging brevity for clarity.

Message 138 is kept as-is, as it is not yet covered by any tests.

Message 240 is kep as-is, as it is unreachable.

lint: in C99 mode, make implicit function declarations an error

In tree.c 1.294 from 2021-06-28, I had already tried this, but at that
time, there were too many implicit function definitions in the NetBSD
tree. Most of them were GCC builtins, which lint did not recognize.
Therefore I had to revert to a warning in tree.c 1.302 from 2021-06-30.

In the meantime, lint has learnt to recognize compiler builtins, see
is_compiler_builtin, so try again now. The build logs from x86_64,
i386, sparc and sparc64 show no more implicit function declarations.

lint: add __sync_ and _mm_ as prefixes for builtin functions

These two additions cover all cases that occur in the current NetBSD
build on x86_64. This allows build_name to use the usual pattern 'if
Sflag then error else if sflag then warning'. That function currently
issues a warning in C99 as well, even though C99 prohibits implicit
function declarations.

lint: do not warn about use of implicitly declared GCC builtins

lint: in C99 mode, only warn about implicit function declarations

Since tree.c 1.294 from 2021-06-28 (two days ago), lint errored out on
an implicit function declaration. In principle it is correct to do so
since C99 requires it, but in practice there are a several functions
that are not declared in the translation unit itself since they are
provided by the compiler. Typical examples for GCC and Clang are the
various functions named '__builtin_*' and '__atomic_*'.

For now, only warn about these but don't error out.

lint: mention the name of an implicitly declared function

In the regular NetBSD builds, this happened in swab.c:65. That line
contains __predict_false, which may or may not be a macro. In other
cases, there may be more than one function call in a single line.

tests/lint: extend test for message 215 about implicit function

lint: fix type name in message 101 for wrong member name

tests/lint: extend and explain test for implicit function declaration

lint: in C99 mode, complain about implicitly declared functions

C99, foreword, p5, item 22 lists among the major changes from C90:
"remove implicit function declaration".

lint: force each test to declare the expected diagnostics

By listing the expected diagnostics directly at the code that triggers
the diagnostics, it is easier to cross-check whether the diagnostics
make sense.

No functional change to lint itself.

lint: add a test for each message produced by lint1

Having a test for each message ensures that upcoming refactorings don't
break the basic functionality. Adding the tests will also discover
previously unknown bugs in lint.

The tests ensure that every lint message can actually be triggered, and
they demonstrate how to do so. Having a separate file for each test
leaves enough space for documenting historical anecdotes, rationale or
edge cases, keeping them away from the source code.

The interesting details of this commit are in Makefile and
t_integration.sh. All other files are just auto-generated.

When running the tests as part of ATF, they are packed together as a
single test case. Conceptually, it would have been better to have each
test as a separate test case, but ATF quickly becomes very slow as soon
as a test program defines too many test cases, and 50 is already too
many. The time complexity is O(n^2), not O(n) as one would expect.
It's the same problem as in tests/usr.bin/make, which has over 300 test
cases as well.

lint: in C99 mode, make implicit function declarations an error

In tree.c 1.294 from 2021-06-28, I had already tried this, but at that
time, there were too many implicit function definitions in the NetBSD
tree. Most of them were GCC builtins, which lint did not recognize.
Therefore I had to revert to a warning in tree.c 1.302 from 2021-06-30.

In the meantime, lint has learnt to recognize compiler builtins, see
is_compiler_builtin, so try again now. The build logs from x86_64,
i386, sparc and sparc64 show no more implicit function declarations.

lint: add __sync_ and _mm_ as prefixes for builtin functions

These two additions cover all cases that occur in the current NetBSD
build on x86_64. This allows build_name to use the usual pattern 'if
Sflag then error else if sflag then warning'. That function currently
issues a warning in C99 as well, even though C99 prohibits implicit
function declarations.

lint: do not warn about use of implicitly declared GCC builtins

lint: in C99 mode, only warn about implicit function declarations

Since tree.c 1.294 from 2021-06-28 (two days ago), lint errored out on
an implicit function declaration. In principle it is correct to do so
since C99 requires it, but in practice there are a several functions
that are not declared in the translation unit itself since they are
provided by the compiler. Typical examples for GCC and Clang are the
various functions named '__builtin_*' and '__atomic_*'.

For now, only warn about these but don't error out.

lint: mention the name of an implicitly declared function

In the regular NetBSD builds, this happened in swab.c:65. That line
contains __predict_false, which may or may not be a macro. In other
cases, there may be more than one function call in a single line.

tests/lint: extend test for message 215 about implicit function

lint: fix type name in message 101 for wrong member name

tests/lint: extend and explain test for implicit function declaration

lint: in C99 mode, complain about implicitly declared functions

C99, foreword, p5, item 22 lists among the major changes from C90:
"remove implicit function declaration".

lint: force each test to declare the expected diagnostics

By listing the expected diagnostics directly at the code that triggers
the diagnostics, it is easier to cross-check whether the diagnostics
make sense.

No functional change to lint itself.

lint: add a test for each message produced by lint1

Having a test for each message ensures that upcoming refactorings don't
break the basic functionality. Adding the tests will also discover
previously unknown bugs in lint.

The tests ensure that every lint message can actually be triggered, and
they demonstrate how to do so. Having a separate file for each test
leaves enough space for documenting historical anecdotes, rationale or
edge cases, keeping them away from the source code.

The interesting details of this commit are in Makefile and
t_integration.sh. All other files are just auto-generated.

When running the tests as part of ATF, they are packed together as a
single test case. Conceptually, it would have been better to have each
test as a separate test case, but ATF quickly becomes very slow as soon
as a test program defines too many test cases, and 50 is already too
many. The time complexity is O(n^2), not O(n) as one would expect.
It's the same problem as in tests/usr.bin/make, which has over 300 test
cases as well.

lint: do not warn about use of implicitly declared GCC builtins

lint: in C99 mode, only warn about implicit function declarations

Since tree.c 1.294 from 2021-06-28 (two days ago), lint errored out on
an implicit function declaration. In principle it is correct to do so
since C99 requires it, but in practice there are a several functions
that are not declared in the translation unit itself since they are
provided by the compiler. Typical examples for GCC and Clang are the
various functions named '__builtin_*' and '__atomic_*'.

For now, only warn about these but don't error out.

lint: mention the name of an implicitly declared function

In the regular NetBSD builds, this happened in swab.c:65. That line
contains __predict_false, which may or may not be a macro. In other
cases, there may be more than one function call in a single line.

tests/lint: extend test for message 215 about implicit function

lint: fix type name in message 101 for wrong member name

tests/lint: extend and explain test for implicit function declaration

lint: in C99 mode, complain about implicitly declared functions

C99, foreword, p5, item 22 lists among the major changes from C90:
"remove implicit function declaration".

lint: force each test to declare the expected diagnostics

By listing the expected diagnostics directly at the code that triggers
the diagnostics, it is easier to cross-check whether the diagnostics
make sense.

No functional change to lint itself.

lint: add a test for each message produced by lint1

Having a test for each message ensures that upcoming refactorings don't
break the basic functionality. Adding the tests will also discover
previously unknown bugs in lint.

The tests ensure that every lint message can actually be triggered, and
they demonstrate how to do so. Having a separate file for each test
leaves enough space for documenting historical anecdotes, rationale or
edge cases, keeping them away from the source code.

The interesting details of this commit are in Makefile and
t_integration.sh. All other files are just auto-generated.

When running the tests as part of ATF, they are packed together as a
single test case. Conceptually, it would have been better to have each
test as a separate test case, but ATF quickly becomes very slow as soon
as a test program defines too many test cases, and 50 is already too
many. The time complexity is O(n^2), not O(n) as one would expect.
It's the same problem as in tests/usr.bin/make, which has over 300 test
cases as well.

lint: in C99 mode, complain about implicitly declared functions

C99, foreword, p5, item 22 lists among the major changes from C90:
"remove implicit function declaration".

lint: force each test to declare the expected diagnostics

By listing the expected diagnostics directly at the code that triggers
the diagnostics, it is easier to cross-check whether the diagnostics
make sense.

No functional change to lint itself.

lint: add a test for each message produced by lint1

Having a test for each message ensures that upcoming refactorings don't
break the basic functionality. Adding the tests will also discover
previously unknown bugs in lint.

The tests ensure that every lint message can actually be triggered, and
they demonstrate how to do so. Having a separate file for each test
leaves enough space for documenting historical anecdotes, rationale or
edge cases, keeping them away from the source code.

The interesting details of this commit are in Makefile and
t_integration.sh. All other files are just auto-generated.

When running the tests as part of ATF, they are packed together as a
single test case. Conceptually, it would have been better to have each
test as a separate test case, but ATF quickly becomes very slow as soon
as a test program defines too many test cases, and 50 is already too
many. The time complexity is O(n^2), not O(n) as one would expect.
It's the same problem as in tests/usr.bin/make, which has over 300 test
cases as well.

lint: force each test to declare the expected diagnostics

By listing the expected diagnostics directly at the code that triggers
the diagnostics, it is easier to cross-check whether the diagnostics
make sense.

No functional change to lint itself.

lint: add a test for each message produced by lint1

Having a test for each message ensures that upcoming refactorings don't
break the basic functionality. Adding the tests will also discover
previously unknown bugs in lint.

The tests ensure that every lint message can actually be triggered, and
they demonstrate how to do so. Having a separate file for each test
leaves enough space for documenting historical anecdotes, rationale or
edge cases, keeping them away from the source code.

The interesting details of this commit are in Makefile and
t_integration.sh. All other files are just auto-generated.

When running the tests as part of ATF, they are packed together as a
single test case. Conceptually, it would have been better to have each
test as a separate test case, but ATF quickly becomes very slow as soon
as a test program defines too many test cases, and 50 is already too
many. The time complexity is O(n^2), not O(n) as one would expect.
It's the same problem as in tests/usr.bin/make, which has over 300 test
cases as well.

lint: add a test for each message produced by lint1

Having a test for each message ensures that upcoming refactorings don't
break the basic functionality. Adding the tests will also discover
previously unknown bugs in lint.

The tests ensure that every lint message can actually be triggered, and
they demonstrate how to do so. Having a separate file for each test
leaves enough space for documenting historical anecdotes, rationale or
edge cases, keeping them away from the source code.

The interesting details of this commit are in Makefile and
t_integration.sh. All other files are just auto-generated.

When running the tests as part of ATF, they are packed together as a
single test case. Conceptually, it would have been better to have each
test as a separate test case, but ATF quickly becomes very slow as soon
as a test program defines too many test cases, and 50 is already too
many. The time complexity is O(n^2), not O(n) as one would expect.
It's the same problem as in tests/usr.bin/make, which has over 300 test
cases as well.