[binutils-gdb] gas: scfi: untraceable control flow should be a hard error

[Indu Bhagat]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=91cdbed4d7b3acff951e0f21008a7775a7f23c20

commit 91cdbed4d7b3acff951e0f21008a7775a7f23c20
Author: Indu Bhagat <indu.bhagat@oracle.com>
Date:   Fri Jan 26 10:30:18 2024 -0800

    gas: scfi: untraceable control flow should be a hard error
    
    PR gas/31284
    
    Currently, if an indirect jump is seen, GCFG (a CFG of ginsns) cannot be
    created, and the SCFI machinery bails out with a warning:
      "Warning: Untraceable control flow for func 'foo'; Skipping SCFI"
    
    It is, however, better suited if this is a hard error.  Change it to a
    hard error.  Also change the message to skip mentioning "SCFI", because
    the error itself may also useful when ginsns are used for other passes
    (distinct from SCFI) involving GCFG, like a pass to detect if there is
    unreachable code.  Hence, simply say:
      "Error: untraceable control flow for func 'foo'"
    
    gas/
    PR gas/31284
            * ginsn.c (ginsn_data_end): Use as_bad instead of as_warn.
    
    gas/testsuite/
    PR gas/31284
            * gas/scfi/x86_64/ginsn-cofi-1.l: Adjust to the expected output
            in case of errors.
            * gas/scfi/x86_64/scfi-unsupported-cfg-1.l: Error not Warning.

Diff:
---
 gas/ginsn.c                                            |  4 ++--
 gas/testsuite/gas/scfi/x86_64/ginsn-cofi-1.l           | 18 ++++++++++--------
 gas/testsuite/gas/scfi/x86_64/scfi-unsupported-cfg-1.l |  2 +-
 3 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/gas/ginsn.c b/gas/ginsn.c
index 5f6a67ce4f2..661f51d23c5 100644
--- a/gas/ginsn.c
+++ b/gas/ginsn.c
@@ -1161,8 +1161,8 @@ ginsn_data_end (const symbolS *label)
   /* Build the cfg of ginsn(s) of the function.  */
   if (!frchain_now->frch_ginsn_data->gcfg_apt_p)
     {
-      as_warn (_("Untraceable control flow for func '%s'; Skipping SCFI"),
-	       S_GET_NAME (func));
+      as_bad (_("untraceable control flow for func '%s'"),
+	      S_GET_NAME (func));
       goto end;
     }
 
diff --git a/gas/testsuite/gas/scfi/x86_64/ginsn-cofi-1.l b/gas/testsuite/gas/scfi/x86_64/ginsn-cofi-1.l
index fee76f9cc9b..ab6b50d47e8 100644
--- a/gas/testsuite/gas/scfi/x86_64/ginsn-cofi-1.l
+++ b/gas/testsuite/gas/scfi/x86_64/ginsn-cofi-1.l
@@ -1,3 +1,5 @@
+.*: Assembler messages:
+.*:20: Error: untraceable control flow for func 'foo'
 GAS LISTING .*
 
 
@@ -12,23 +14,23 @@ GAS LISTING .*
    8              	ginsn: SYM FUNC_BEGIN
    9              	foo:
    9              	ginsn: SYM foo
-  10 0000 4801D0   		addq    %rdx, %rax
+  10 \?\?\?\? 4801D0   		addq    %rdx, %rax
   10              	ginsn: ADD %r1, %r0, %r0
-  11 0003 E200     		loop    foo
+  11 \?\?\?\? E200     		loop    foo
   11              	ginsn: JCC 
-  12 0005 3EFFE0   		notrack jmp     \*%rax
+  12 \?\?\?\? 3EFFE0   		notrack jmp     \*%rax
   12              	ginsn: JMP %r0, 
-  13 0008 41FFD0   		call    \*%r8
+  13 \?\?\?\? 41FFD0   		call    \*%r8
   13              	ginsn: CALL
-  14 000b 67E305   		jecxz   .L179
+  14 \?\?\?\? 67E305   		jecxz   .L179
   14              	ginsn: JCC 
-  15 000e FF6730   		jmp     \*48\(%rdi\)
+  15 \?\?\?\? FF6730   		jmp     \*48\(%rdi\)
   15              	ginsn: JMP %r5, 
-  16 0011 7000     		jo      .L179
+  16 \?\?\?\? 7000     		jo      .L179
   16              	ginsn: JCC 
   17              	.L179:
   17              	ginsn: SYM .L179
-  18 0013 C3       		ret
+  18 \?\?\?\? C3       		ret
   18              	ginsn: RET
   19              	.LFE0:
   19              	ginsn: SYM .LFE0
diff --git a/gas/testsuite/gas/scfi/x86_64/scfi-unsupported-cfg-1.l b/gas/testsuite/gas/scfi/x86_64/scfi-unsupported-cfg-1.l
index 1e138a102fe..c59ba93df45 100644
--- a/gas/testsuite/gas/scfi/x86_64/scfi-unsupported-cfg-1.l
+++ b/gas/testsuite/gas/scfi/x86_64/scfi-unsupported-cfg-1.l
@@ -1,3 +1,3 @@
 .*Assembler messages:
 .*50: Warning: SCFI ignores most user-specified CFI directives
-.*52: Warning: Untraceable control flow for func 'foo'; Skipping SCFI
+.*52: Error: untraceable control flow for func 'foo'