make: on error, print the targets to be made

This helps to understand situations with several nested sub-makes in
varying directories.

make: all command line overrides go in .MAKEOVERRIDES

Not all variables that start with '.' are internals,
and unless they are explicitly flagged as internal should go
into .MAKEOVERRIDES

Update varname-dot-makeoverrides to check this.

Also avoid using SCOPE_CMDLINE when ReadOnly will do.

Add .MAKE.JOBS.C to indicate wether -jC is supported

make: .SYSPATH: to add dirs to sysIncPath

.SYSPATH: with no sources will clear sysIncPath
otherwise sources are added

Reviewed by: rillig

make: avoid trailing whitespace in debug log for variables

Since trailing whitespace is invisible, describe the variable value in
words to make it visible.

make: remove overengineered Enum_ValueToString

For printing the status of a GNode, there was already made_name (now
renamed to GNodeMade_Name), which prints user-friendly text instead of
the bare enum constant names.

To do this change confidently, I first had to demonstrate that the
output really affects something other than just the word "UNMADE". There
had not been a test for that case before, and the test immediately
discovered a bug in the -dg2 and -dg3 options. This bug is one of the
oldest in make, dating back to at least 1993.

make: when exiting due to an error, print graph information

The code now does what the manual page has been promising since at least
1993.

make: demonstrate that neither -dg2 nor -dg3 produces debug output

make(1): add tests for each debug option

make: all command line overrides go in .MAKEOVERRIDES

Not all variables that start with '.' are internals,
and unless they are explicitly flagged as internal should go
into .MAKEOVERRIDES

Update varname-dot-makeoverrides to check this.

Also avoid using SCOPE_CMDLINE when ReadOnly will do.

Add .MAKE.JOBS.C to indicate wether -jC is supported

make: .SYSPATH: to add dirs to sysIncPath

.SYSPATH: with no sources will clear sysIncPath
otherwise sources are added

Reviewed by: rillig

make: avoid trailing whitespace in debug log for variables

Since trailing whitespace is invisible, describe the variable value in
words to make it visible.

make: remove overengineered Enum_ValueToString

For printing the status of a GNode, there was already made_name (now
renamed to GNodeMade_Name), which prints user-friendly text instead of
the bare enum constant names.

To do this change confidently, I first had to demonstrate that the
output really affects something other than just the word "UNMADE". There
had not been a test for that case before, and the test immediately
discovered a bug in the -dg2 and -dg3 options. This bug is one of the
oldest in make, dating back to at least 1993.

make: when exiting due to an error, print graph information

The code now does what the manual page has been promising since at least
1993.

make: demonstrate that neither -dg2 nor -dg3 produces debug output

make(1): add tests for each debug option

Add .MAKE.JOBS.C to indicate wether -jC is supported

make: .SYSPATH: to add dirs to sysIncPath

.SYSPATH: with no sources will clear sysIncPath
otherwise sources are added

Reviewed by: rillig

make: avoid trailing whitespace in debug log for variables

Since trailing whitespace is invisible, describe the variable value in
words to make it visible.

make: remove overengineered Enum_ValueToString

For printing the status of a GNode, there was already made_name (now
renamed to GNodeMade_Name), which prints user-friendly text instead of
the bare enum constant names.

To do this change confidently, I first had to demonstrate that the
output really affects something other than just the word "UNMADE". There
had not been a test for that case before, and the test immediately
discovered a bug in the -dg2 and -dg3 options. This bug is one of the
oldest in make, dating back to at least 1993.

make: when exiting due to an error, print graph information

The code now does what the manual page has been promising since at least
1993.

make: demonstrate that neither -dg2 nor -dg3 produces debug output

make(1): add tests for each debug option

make: .SYSPATH: to add dirs to sysIncPath

.SYSPATH: with no sources will clear sysIncPath
otherwise sources are added

Reviewed by: rillig

make: avoid trailing whitespace in debug log for variables

Since trailing whitespace is invisible, describe the variable value in
words to make it visible.

make: remove overengineered Enum_ValueToString

For printing the status of a GNode, there was already made_name (now
renamed to GNodeMade_Name), which prints user-friendly text instead of
the bare enum constant names.

To do this change confidently, I first had to demonstrate that the
output really affects something other than just the word "UNMADE". There
had not been a test for that case before, and the test immediately
discovered a bug in the -dg2 and -dg3 options. This bug is one of the
oldest in make, dating back to at least 1993.

make: when exiting due to an error, print graph information

The code now does what the manual page has been promising since at least
1993.

make: demonstrate that neither -dg2 nor -dg3 produces debug output

make(1): add tests for each debug option

make: avoid trailing whitespace in debug log for variables

Since trailing whitespace is invisible, describe the variable value in
words to make it visible.

make: remove overengineered Enum_ValueToString

For printing the status of a GNode, there was already made_name (now
renamed to GNodeMade_Name), which prints user-friendly text instead of
the bare enum constant names.

To do this change confidently, I first had to demonstrate that the
output really affects something other than just the word "UNMADE". There
had not been a test for that case before, and the test immediately
discovered a bug in the -dg2 and -dg3 options. This bug is one of the
oldest in make, dating back to at least 1993.

make: when exiting due to an error, print graph information

The code now does what the manual page has been promising since at least
1993.

make: demonstrate that neither -dg2 nor -dg3 produces debug output

make(1): add tests for each debug option

make: remove overengineered Enum_ValueToString

For printing the status of a GNode, there was already made_name (now
renamed to GNodeMade_Name), which prints user-friendly text instead of
the bare enum constant names.

To do this change confidently, I first had to demonstrate that the
output really affects something other than just the word "UNMADE". There
had not been a test for that case before, and the test immediately
discovered a bug in the -dg2 and -dg3 options. This bug is one of the
oldest in make, dating back to at least 1993.

make: when exiting due to an error, print graph information

The code now does what the manual page has been promising since at least
1993.

make: demonstrate that neither -dg2 nor -dg3 produces debug output

make(1): add tests for each debug option