[gcc(refs/vendors/ARM/heads/arm-9-branch)] Fix ICE with cast of division by zero (PR c/93348).

[Joey Ye]

https://gcc.gnu.org/g:a11e92c4e7fd660b0f5ea2095439dc33738c69a5

commit a11e92c4e7fd660b0f5ea2095439dc33738c69a5
Author: Joseph Myers <joseph@codesourcery.com>
Date:   Wed Jan 22 17:26:10 2020 +0000

    Fix ICE with cast of division by zero (PR c/93348).
    
    Bug 93348 reports an ICE on certain cases of casts of expressions that
    may appear only in unevaluated parts of integer constant expressions,
    arising from the generation of nested C_MAYBE_CONST_EXPRs.  This patch
    fixes it by adding a call to remove_c_maybe_const_expr in the
    integer-operands case, as is done in other similar cases.
    
    Bootstrapped with no regressions for x86_64-pc-linux-gnu.
    
    	PR c/93348
    gcc/c:
    	* c-typeck.c (build_c_cast): Call remove_c_maybe_const_expr on
    	argument with integer operands.
    
    gcc/testsuite:
    	* gcc.c-torture/compile/pr93348-1.c: New test.
    
    (cherry picked from commit ac68e287fc2e939ae6b45ba7ff04e493982b7f62)

Diff:
---
 gcc/c/ChangeLog                                 | 9 +++++++++
 gcc/c/c-typeck.c                                | 2 ++
 gcc/testsuite/ChangeLog                         | 8 ++++++++
 gcc/testsuite/gcc.c-torture/compile/pr93348-1.c | 5 +++++
 4 files changed, 24 insertions(+)

diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog
index 64f0275..b17ed98 100644
--- a/gcc/c/ChangeLog
+++ b/gcc/c/ChangeLog
@@ -1,3 +1,12 @@
+2020-01-22  Joseph Myers  <joseph@codesourcery.com>
+
+	Backport from mainline:
+	2020-01-22  Joseph Myers  <joseph@codesourcery.com>
+
+	PR c/93348
+	* c-typeck.c (build_c_cast): Call remove_c_maybe_const_expr on
+	argument with integer operands.
+
 2020-01-15  Joseph Myers  <joseph@codesourcery.com>
 
 	Backport from mainline:
diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c
index 5d5231d..c0582a5 100644
--- a/gcc/c/c-typeck.c
+++ b/gcc/c/c-typeck.c
@@ -5708,6 +5708,8 @@ build_c_cast (location_t loc, tree type, tree expr)
     expr = TREE_OPERAND (expr, 0);
 
   value = expr;
+  if (int_operands)
+    value = remove_c_maybe_const_expr (value);
 
   if (type == error_mark_node || expr == error_mark_node)
     return error_mark_node;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 24dda65..d76c059 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2020-01-22  Joseph Myers  <joseph@codesourcery.com>
+
+	Backport from mainline:
+	2020-01-22  Joseph Myers  <joseph@codesourcery.com>
+
+	PR c/93348
+	* gcc.c-torture/compile/pr93348-1.c: New test.
+
 2020-01-21  Jerry DeLisle  <jvdelisle@gcc.gnu.org>
 
 	Backport from mainline
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr93348-1.c b/gcc/testsuite/gcc.c-torture/compile/pr93348-1.c
new file mode 100644
index 0000000..d2edec5
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr93348-1.c
@@ -0,0 +1,5 @@
+int
+ya (void)
+{
+  return (long int) (1 / 0);
+}