[binutils-gdb] eh static data

[Alan Modra <amodra@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=4148b4fe9fd15607aad8b082c7b724f355f2da64

commit 4148b4fe9fd15607aad8b082c7b724f355f2da64
Author: Alan Modra <amodra@gmail.com>
Date:   Fri Mar 10 10:05:44 2023 +1030

    eh static data
    
    Fix another case of oss-fuzz tripping over gas static state,
    ie. starting over testing another input file with rubbish left
    uncleared in bss.  size_end_sym pointed at garbage.
    
            * ehopt.c (get_cie_info): Delete forward declaration.
            (struct frame_data): Move to file scope.
            (frame): New static, packaged..
            (check_eh_frame): ..eh_frame_data and debug_frame_data.
            (eh_begin): New function.
            * as.c (gas_init): Call eh_begin.
            * as.h (eh_begin): Declare.

Diff:
---
 gas/as.c    |  1 +
 gas/as.h    |  1 +
 gas/ehopt.c | 50 +++++++++++++++++++++++++++++---------------------
 3 files changed, 31 insertions(+), 21 deletions(-)

diff --git a/gas/as.c b/gas/as.c
index 62f32fc865a..a18438c2542 100644
--- a/gas/as.c
+++ b/gas/as.c
@@ -1328,6 +1328,7 @@ gas_init (void)
   read_begin ();
   input_scrub_begin ();
   expr_begin ();
+  eh_begin ();
 
   int macro_strip_at = 0;
 #ifdef TC_I960
diff --git a/gas/as.h b/gas/as.h
index 4c5fa9ecf7d..4d3a71410ff 100644
--- a/gas/as.h
+++ b/gas/as.h
@@ -538,6 +538,7 @@ int check_eh_frame (struct expressionS *, unsigned int *);
 int eh_frame_estimate_size_before_relax (fragS *);
 int eh_frame_relax_frag (fragS *);
 void eh_frame_convert_frag (fragS *);
+void eh_begin (void);
 int generic_force_reloc (struct fix *);
 
 /* SFrame FRE optimization.  */
diff --git a/gas/ehopt.c b/gas/ehopt.c
index 268554d89a7..feea61b9223 100644
--- a/gas/ehopt.c
+++ b/gas/ehopt.c
@@ -94,8 +94,6 @@ struct cie_info
   int z_augmentation;
 };
 
-static int get_cie_info (struct cie_info *);
-
 /* Extract information from the CIE.  */
 
 static int
@@ -238,6 +236,27 @@ enum frame_state
   state_error,
 };
 
+struct frame_data
+{
+  enum frame_state state;
+
+  int cie_info_ok;
+  struct cie_info cie_info;
+
+  symbolS *size_end_sym;
+  fragS *loc4_frag;
+  int loc4_fix;
+
+  int aug_size;
+  int aug_shift;
+};
+
+static struct eh_state
+{
+  struct frame_data eh_data;
+  struct frame_data debug_data;
+} frame;
+
 /* This function is called from emit_expr.  It looks for cases which
    we can optimize.
 
@@ -254,23 +273,6 @@ enum frame_state
 int
 check_eh_frame (expressionS *exp, unsigned int *pnbytes)
 {
-  struct frame_data
-  {
-    enum frame_state state;
-
-    int cie_info_ok;
-    struct cie_info cie_info;
-
-    symbolS *size_end_sym;
-    fragS *loc4_frag;
-    int loc4_fix;
-
-    int aug_size;
-    int aug_shift;
-  };
-
-  static struct frame_data eh_frame_data;
-  static struct frame_data debug_frame_data;
   struct frame_data *d;
 
   /* Don't optimize.  */
@@ -285,9 +287,9 @@ check_eh_frame (expressionS *exp, unsigned int *pnbytes)
   /* Select the proper section data.  */
   if (startswith (segment_name (now_seg), ".eh_frame")
       && segment_name (now_seg)[9] != '_')
-    d = &eh_frame_data;
+    d = &frame.eh_data;
   else if (startswith (segment_name (now_seg), ".debug_frame"))
-    d = &debug_frame_data;
+    d = &frame.debug_data;
   else
     return 0;
 
@@ -570,3 +572,9 @@ eh_frame_convert_frag (fragS *frag)
   frag->fr_subtype = 0;
   frag->fr_offset = 0;
 }
+
+void
+eh_begin (void)
+{
+  memset (&frame, 0, sizeof (frame));
+}