Leave a suppressed note out of its error [GH #405]

src/error.c

@@ -7679,10 +7679,25 @@ void add_more_info_list(a_diagnostic_ptr	dp,
 			a_diag_list_ptr		dlp)
 /*
 Add the list of "more information" diagnostics specified by dlp to the
-primary diagnostic dp.
+primary diagnostic dp.  An entry whose severity is es_none was suppressed
+(by --diag_suppress or a diagnostic pragma for its error number): it is not
+added, as a suppressed diagnostic is never displayed.  The routines that write
+a diagnostic have no severity to give such an entry.
 */
 {
-  dp->more_info = *dlp;
+  a_diagnostic_ptr	mi_dp;
+  a_diagnostic_ptr	next_mi_dp;
+
+  clear_diag_list(&dp->more_info);
+  for (mi_dp = dlp->head; mi_dp != NULL; mi_dp = next_mi_dp) {
+    next_mi_dp = mi_dp->next;
+    mi_dp->next = NULL;
+    if (mi_dp->severity == es_none) {
+      free_diagnostic(mi_dp);
+    } else {
+      append_to_diag_list(&dp->more_info, mi_dp);
+    }  /* if */
+  }  /* for */
   /* Clear the entries in the list passed in. */
   clear_diag_list(dlp);
 }  /* add_more_info_list */

src/pending_changes/gh-405-diag-suppress-note.txt

@@ -0,0 +1,19 @@
+[GH #405]
+A suppressed note of a constant-evaluation error no longer stops the front end
+
+When constant evaluation fails, the front end attaches notes to the error
+"expression must have a constant value": "shift count is too large" (#63),
+"shift count is negative" (#62), "division by zero" (#39) and "integer
+operation result is out of range" (#61) among them.  A note takes the severity
+of its own error number, so when --diag_suppress or a diag_suppress pragma
+named the number of the note, the note had a severity that could not be
+displayed and the front end stopped with an internal error (in the text
+output; the SARIF output listed the suppressed note as a related location):
+
+  constexpr int z = 1 << 32;
+    // --diag_suppress=63: internal error: assertion failed:
+    // determine_severity_code: bad severity
+
+A suppressed note is now left out of the diagnostic, as a suppressed
+diagnostic always is, in the SARIF output too.  The error itself is still
+reported.

tests/tests/changes/.gh-405.rto/default.1.1.txt

@@ -0,0 +1,46 @@
+fe_only -DTEST_NUMBER=1 --c++20 --diag_suppress=39,62,63 Test_name.c
+"Test_name.c", line 26: error: expression must have a constant value
+  constexpr int shift_too_large = 1 << 32;
+                                  ^
+
+"Test_name.c", line 27: error: expression must have a constant value
+  constexpr int shift_negative = 1 << -1;
+                                 ^
+
+"Test_name.c", line 28: error: expression must have a constant value
+  constexpr int divide_by_zero = 10 / 0;
+                                 ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                             ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                                         ^
+
+"Test_name.c", line 32: error: expression must have a constant value
+  int array_bound[1 << 32];
+                  ^
+
+"Test_name.c", line 34: error: expression must have a constant value
+  static_assert((1 << 33) == 0);
+                ^
+
+"Test_name.c", line 37: error: expression must have a constant value
+  S<1 << 34> s;
+    ^
+
+"Test_name.c", line 26: warning: variable "shift_too_large" was declared but never referenced
+  constexpr int shift_too_large = 1 << 32;
+                ^
+
+"Test_name.c", line 27: warning: variable "shift_negative" was declared but never referenced
+  constexpr int shift_negative = 1 << -1;
+                ^
+
+"Test_name.c", line 28: warning: variable "divide_by_zero" was declared but never referenced
+  constexpr int divide_by_zero = 10 / 0;
+                ^
+
+8 errors detected in the compilation of "Test_name.c".

tests/tests/changes/.gh-405.rto/default.2.1.txt

@@ -0,0 +1,72 @@
+fe_only -DTEST_NUMBER=2 --c++20 --diag_suppress=39 Test_name.c
+"Test_name.c", line 26: error: expression must have a constant value
+  constexpr int shift_too_large = 1 << 32;
+                                  ^
+"Test_name.c", line 26: note: shift count is too large
+  constexpr int shift_too_large = 1 << 32;
+                                       ^
+
+"Test_name.c", line 27: error: expression must have a constant value
+  constexpr int shift_negative = 1 << -1;
+                                 ^
+"Test_name.c", line 27: note: shift count is negative
+  constexpr int shift_negative = 1 << -1;
+                                      ^
+
+"Test_name.c", line 28: error: expression must have a constant value
+  constexpr int divide_by_zero = 10 / 0;
+                                 ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                             ^
+"Test_name.c", line 30: note: shift count is too large
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                  ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                                         ^
+
+"Test_name.c", line 32: error: expression must have a constant value
+  int array_bound[1 << 32];
+                  ^
+"Test_name.c", line 32: note: shift count is too large
+  int array_bound[1 << 32];
+                       ^
+
+"Test_name.c", line 34: error: expression must have a constant value
+  static_assert((1 << 33) == 0);
+                ^
+"Test_name.c", line 34: note: shift count is too large
+  static_assert((1 << 33) == 0);
+                      ^
+
+"Test_name.c", line 37: error: expression must have a constant value
+  S<1 << 34> s;
+    ^
+"Test_name.c", line 37: note: shift count is too large
+  S<1 << 34> s;
+         ^
+
+"Test_name.c", line 42: warning: shift count is too large
+    return (x << 40) + (x / 0) + (x << -1);
+                 ^
+
+"Test_name.c", line 42: warning: shift count is negative
+    return (x << 40) + (x / 0) + (x << -1);
+                                       ^
+
+"Test_name.c", line 26: warning: variable "shift_too_large" was declared but never referenced
+  constexpr int shift_too_large = 1 << 32;
+                ^
+
+"Test_name.c", line 27: warning: variable "shift_negative" was declared but never referenced
+  constexpr int shift_negative = 1 << -1;
+                ^
+
+"Test_name.c", line 28: warning: variable "divide_by_zero" was declared but never referenced
+  constexpr int divide_by_zero = 10 / 0;
+                ^
+
+8 errors detected in the compilation of "Test_name.c".

tests/tests/changes/.gh-405.rto/default.3.1.txt

@@ -0,0 +1,75 @@
+fe_only -DTEST_NUMBER=3 --c++20 --diag_suppress=62 Test_name.c
+"Test_name.c", line 26: error: expression must have a constant value
+  constexpr int shift_too_large = 1 << 32;
+                                  ^
+"Test_name.c", line 26: note: shift count is too large
+  constexpr int shift_too_large = 1 << 32;
+                                       ^
+
+"Test_name.c", line 27: error: expression must have a constant value
+  constexpr int shift_negative = 1 << -1;
+                                 ^
+
+"Test_name.c", line 28: error: expression must have a constant value
+  constexpr int divide_by_zero = 10 / 0;
+                                 ^
+"Test_name.c", line 28: note: division by zero
+  constexpr int divide_by_zero = 10 / 0;
+                                    ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                             ^
+"Test_name.c", line 30: note: shift count is too large
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                  ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                                         ^
+"Test_name.c", line 30: note: division by zero
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                                            ^
+
+"Test_name.c", line 32: error: expression must have a constant value
+  int array_bound[1 << 32];
+                  ^
+"Test_name.c", line 32: note: shift count is too large
+  int array_bound[1 << 32];
+                       ^
+
+"Test_name.c", line 34: error: expression must have a constant value
+  static_assert((1 << 33) == 0);
+                ^
+"Test_name.c", line 34: note: shift count is too large
+  static_assert((1 << 33) == 0);
+                      ^
+
+"Test_name.c", line 37: error: expression must have a constant value
+  S<1 << 34> s;
+    ^
+"Test_name.c", line 37: note: shift count is too large
+  S<1 << 34> s;
+         ^
+
+"Test_name.c", line 42: warning: shift count is too large
+    return (x << 40) + (x / 0) + (x << -1);
+                 ^
+
+"Test_name.c", line 42: warning: division by zero
+    return (x << 40) + (x / 0) + (x << -1);
+                            ^
+
+"Test_name.c", line 26: warning: variable "shift_too_large" was declared but never referenced
+  constexpr int shift_too_large = 1 << 32;
+                ^
+
+"Test_name.c", line 27: warning: variable "shift_negative" was declared but never referenced
+  constexpr int shift_negative = 1 << -1;
+                ^
+
+"Test_name.c", line 28: warning: variable "divide_by_zero" was declared but never referenced
+  constexpr int divide_by_zero = 10 / 0;
+                ^
+
+8 errors detected in the compilation of "Test_name.c".

tests/tests/changes/.gh-405.rto/default.4.1.txt

@@ -0,0 +1,63 @@
+fe_only -DTEST_NUMBER=4 --c++20 --diag_suppress=63 Test_name.c
+"Test_name.c", line 26: error: expression must have a constant value
+  constexpr int shift_too_large = 1 << 32;
+                                  ^
+
+"Test_name.c", line 27: error: expression must have a constant value
+  constexpr int shift_negative = 1 << -1;
+                                 ^
+"Test_name.c", line 27: note: shift count is negative
+  constexpr int shift_negative = 1 << -1;
+                                      ^
+
+"Test_name.c", line 28: error: expression must have a constant value
+  constexpr int divide_by_zero = 10 / 0;
+                                 ^
+"Test_name.c", line 28: note: division by zero
+  constexpr int divide_by_zero = 10 / 0;
+                                    ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                             ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                                         ^
+"Test_name.c", line 30: note: division by zero
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                                            ^
+
+"Test_name.c", line 32: error: expression must have a constant value
+  int array_bound[1 << 32];
+                  ^
+
+"Test_name.c", line 34: error: expression must have a constant value
+  static_assert((1 << 33) == 0);
+                ^
+
+"Test_name.c", line 37: error: expression must have a constant value
+  S<1 << 34> s;
+    ^
+
+"Test_name.c", line 42: warning: division by zero
+    return (x << 40) + (x / 0) + (x << -1);
+                            ^
+
+"Test_name.c", line 42: warning: shift count is negative
+    return (x << 40) + (x / 0) + (x << -1);
+                                       ^
+
+"Test_name.c", line 26: warning: variable "shift_too_large" was declared but never referenced
+  constexpr int shift_too_large = 1 << 32;
+                ^
+
+"Test_name.c", line 27: warning: variable "shift_negative" was declared but never referenced
+  constexpr int shift_negative = 1 << -1;
+                ^
+
+"Test_name.c", line 28: warning: variable "divide_by_zero" was declared but never referenced
+  constexpr int divide_by_zero = 10 / 0;
+                ^
+
+8 errors detected in the compilation of "Test_name.c".

tests/tests/changes/.gh-405.rto/default.5.1.txt

@@ -0,0 +1,82 @@
+fe_only -DTEST_NUMBER=5 --c++20 Test_name.c
+"Test_name.c", line 26: error: expression must have a constant value
+  constexpr int shift_too_large = 1 << 32;
+                                  ^
+"Test_name.c", line 26: note: shift count is too large
+  constexpr int shift_too_large = 1 << 32;
+                                       ^
+
+"Test_name.c", line 27: error: expression must have a constant value
+  constexpr int shift_negative = 1 << -1;
+                                 ^
+"Test_name.c", line 27: note: shift count is negative
+  constexpr int shift_negative = 1 << -1;
+                                      ^
+
+"Test_name.c", line 28: error: expression must have a constant value
+  constexpr int divide_by_zero = 10 / 0;
+                                 ^
+"Test_name.c", line 28: note: division by zero
+  constexpr int divide_by_zero = 10 / 0;
+                                    ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                             ^
+"Test_name.c", line 30: note: shift count is too large
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                  ^
+
+"Test_name.c", line 30: error: expression must have a constant value
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                                         ^
+"Test_name.c", line 30: note: division by zero
+  enum { E_shift_too_large = 1 << 32, E_divide_by_zero = 10 / 0 };
+                                                            ^
+
+"Test_name.c", line 32: error: expression must have a constant value
+  int array_bound[1 << 32];
+                  ^
+"Test_name.c", line 32: note: shift count is too large
+  int array_bound[1 << 32];
+                       ^
+
+"Test_name.c", line 34: error: expression must have a constant value
+  static_assert((1 << 33) == 0);
+                ^
+"Test_name.c", line 34: note: shift count is too large
+  static_assert((1 << 33) == 0);
+                      ^
+
+"Test_name.c", line 37: error: expression must have a constant value
+  S<1 << 34> s;
+    ^
+"Test_name.c", line 37: note: shift count is too large
+  S<1 << 34> s;
+         ^
+
+"Test_name.c", line 42: warning: shift count is too large
+    return (x << 40) + (x / 0) + (x << -1);
+                 ^
+
+"Test_name.c", line 42: warning: division by zero
+    return (x << 40) + (x / 0) + (x << -1);
+                            ^
+
+"Test_name.c", line 42: warning: shift count is negative
+    return (x << 40) + (x / 0) + (x << -1);
+                                       ^
+
+"Test_name.c", line 26: warning: variable "shift_too_large" was declared but never referenced
+  constexpr int shift_too_large = 1 << 32;
+                ^
+
+"Test_name.c", line 27: warning: variable "shift_negative" was declared but never referenced
+  constexpr int shift_negative = 1 << -1;
+                ^
+
+"Test_name.c", line 28: warning: variable "divide_by_zero" was declared but never referenced
+  constexpr int divide_by_zero = 10 / 0;
+                ^
+
+8 errors detected in the compilation of "Test_name.c".