Print which warning-flag controls an emitted warning

Both gcc and clang tell which warning flag a reported warning can be
controlled with, this patch makes ghc do the same. More generally, this
allows for annotated compiler output, where an optional annotation is
displayed in brackets after the severity.

This also adds a new flag `-f(no-)show-warning-groups` to control
whether to show which warning-group (such as `-Wall` or `-Wcompat`)
a warning belongs to. This flag is on by default.

This implements #10752

Reviewed By: quchen, bgamari, hvr

Differential Revision: https://phabricator.haskell.org/D1943

4 files changed, 13 insertions, 13 deletions

diff --git a/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail05.stderr b/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail05.stderr
index 687d6d6eda..90d38fd712 100644
--- a/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail05.stderr
+++ b/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail05.stderr
@@ -1,5 +1,5 @@
 
-overloadedrecfldsfail05.hs:7:16: warning:
+overloadedrecfldsfail05.hs:7:16: warning: [-Wunused-local-binds (in -Wextra, -Wunused-binds)]
     Defined but not used: ‘foo’
 
 <no location info>: error: 
diff --git a/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail06.stderr b/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail06.stderr
index 6a1b939a55..6161755562 100644
--- a/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail06.stderr
+++ b/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail06.stderr
@@ -1,29 +1,29 @@
 [1 of 2] Compiling OverloadedRecFldsFail06_A ( OverloadedRecFldsFail06_A.hs, OverloadedRecFldsFail06_A.o )
 
-OverloadedRecFldsFail06_A.hs:9:15: warning:
+OverloadedRecFldsFail06_A.hs:9:15: warning: [-Wunused-local-binds (in -Wextra, -Wunused-binds)]
     Defined but not used: data constructor ‘MkUnused’
 
-OverloadedRecFldsFail06_A.hs:9:42: warning:
+OverloadedRecFldsFail06_A.hs:9:42: warning: [-Wunused-local-binds (in -Wextra, -Wunused-binds)]
     Defined but not used: ‘unused2’
 
-OverloadedRecFldsFail06_A.hs:9:59: warning:
+OverloadedRecFldsFail06_A.hs:9:59: warning: [-Wunused-local-binds (in -Wextra, -Wunused-binds)]
     Defined but not used: ‘used_locally’
 [2 of 2] Compiling Main             ( overloadedrecfldsfail06.hs, overloadedrecfldsfail06.o )
 
-overloadedrecfldsfail06.hs:7:1: warning:
+overloadedrecfldsfail06.hs:7:1: warning: [-Wunused-imports (in -Wextra)]
     The import of ‘Unused(unused), V(x), U(y), MkV, Unused’
     from module ‘OverloadedRecFldsFail06_A’ is redundant
 
-overloadedrecfldsfail06.hs:8:1: warning:
+overloadedrecfldsfail06.hs:8:1: warning: [-Wunused-imports (in -Wextra)]
     The qualified import of ‘OverloadedRecFldsFail06_A’ is redundant
       except perhaps to import instances from ‘OverloadedRecFldsFail06_A’
     To import instances alone, use: import OverloadedRecFldsFail06_A()
 
-overloadedrecfldsfail06.hs:9:1: warning:
+overloadedrecfldsfail06.hs:9:1: warning: [-Wunused-imports (in -Wextra)]
     The qualified import of ‘V(y)’
     from module ‘OverloadedRecFldsFail06_A’ is redundant
 
-overloadedrecfldsfail06.hs:10:1: warning:
+overloadedrecfldsfail06.hs:10:1: warning: [-Wunused-imports (in -Wextra)]
     The qualified import of ‘U(x), U’
     from module ‘OverloadedRecFldsFail06_A’ is redundant
 
diff --git a/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail11.stderr b/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail11.stderr
index 771a46f10c..dac6d29ef2 100644
--- a/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail11.stderr
+++ b/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail11.stderr
@@ -1,9 +1,9 @@
 [1 of 2] Compiling OverloadedRecFldsFail11_A ( OverloadedRecFldsFail11_A.hs, OverloadedRecFldsFail11_A.o )
 [2 of 2] Compiling Main             ( overloadedrecfldsfail11.hs, overloadedrecfldsfail11.o )
 
-overloadedrecfldsfail11.hs:5:15: warning:
+overloadedrecfldsfail11.hs:5:15: warning: [-Wdeprecations (in -Wdefault)]
     In the use of ‘foo’ (imported from OverloadedRecFldsFail11_A):
     "Warning on a record field"
 
-<no location info>: error:
+<no location info>: error: 
 Failing due to -Werror.
diff --git a/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail12.stderr b/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail12.stderr
index f4a2f7bcfc..7cd9151c56 100644
--- a/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail12.stderr
+++ b/testsuite/tests/overloadedrecflds/should_fail/overloadedrecfldsfail12.stderr
@@ -1,15 +1,15 @@
 [1 of 2] Compiling OverloadedRecFldsFail12_A ( OverloadedRecFldsFail12_A.hs, OverloadedRecFldsFail12_A.o )
 [2 of 2] Compiling Main             ( overloadedrecfldsfail12.hs, overloadedrecfldsfail12.o )
 
-overloadedrecfldsfail12.hs:10:11: warning:
+overloadedrecfldsfail12.hs:10:11: warning: [-Wdeprecations (in -Wdefault)]
     In the use of ‘foo’ (imported from OverloadedRecFldsFail12_A):
     "Deprecated foo"
 
-overloadedrecfldsfail12.hs:10:20: warning:
+overloadedrecfldsfail12.hs:10:20: warning: [-Wdeprecations (in -Wdefault)]
     In the use of ‘bar’ (imported from OverloadedRecFldsFail12_A):
     "Deprecated bar"
 
-overloadedrecfldsfail12.hs:13:5: warning:
+overloadedrecfldsfail12.hs:13:5: warning: [-Wdeprecations (in -Wdefault)]
     In the use of ‘foo’ (imported from OverloadedRecFldsFail12_A):
     "Deprecated foo"