Commit 7b376b1c54

Alex Rønne Petersen <alex@alexrp.com>
2024-10-12 22:44:03
glibc: Emit some fill data for stub symbols, thus giving each a unique address.
This prevents LLVM from...cleverly...merging all of the global variable stub symbols that we emit under certain circumstances. This was observed in practice when using zig-bootstrap for arm-linux-gnueabi(hf).
master
1 parent 7e530c1
Changed files (1)
src
glibc.zig
src/glibc.zig
@@ -938,7 +938,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                     // .globl _Exit_2_2_5
                     // .type _Exit_2_2_5, %function;
                     // .symver _Exit_2_2_5, _Exit@@GLIBC_2.2.5
-                    // _Exit_2_2_5:
+                    // _Exit_2_2_5: .long 0
                     const ver_index = versions_buffer[ver_buf_i];
                     const ver = metadata.all_versions[ver_index];
 
@@ -960,7 +960,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                             \\.globl {s}
                             \\.type {s}, %function;
                             \\.symver {s}, {s}{s}GLIBC_{d}.{d}
-                            \\{s}:
+                            \\{s}: {s} 0
                             \\
                         , .{
                             sym_plus_ver,
@@ -971,6 +971,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                             ver.major,
                             ver.minor,
                             sym_plus_ver,
+                            wordDirective(target),
                         });
                     } else {
                         const sym_plus_ver = if (want_default)
@@ -985,7 +986,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                             \\.globl {s}
                             \\.type {s}, %function;
                             \\.symver {s}, {s}{s}GLIBC_{d}.{d}.{d}
-                            \\{s}:
+                            \\{s}: {s} 0
                             \\
                         , .{
                             sym_plus_ver,
@@ -997,6 +998,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                             ver.minor,
                             ver.patch,
                             sym_plus_ver,
+                            wordDirective(target),
                         });
                     }
                 }
@@ -1103,7 +1105,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                     // .type environ_2_2_5, %object;
                     // .size environ_2_2_5, 4;
                     // .symver environ_2_2_5, environ@@GLIBC_2.2.5
-                    // environ_2_2_5:
+                    // environ_2_2_5: .fill 4, 1, 0
                     const ver_index = versions_buffer[ver_buf_i];
                     const ver = metadata.all_versions[ver_index];
 
@@ -1126,7 +1128,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                             \\.type {s}, %object;
                             \\.size {s}, {d};
                             \\.symver {s}, {s}{s}GLIBC_{d}.{d}
-                            \\{s}:
+                            \\{s}: .fill {d}, 1, 0
                             \\
                         , .{
                             sym_plus_ver,
@@ -1139,6 +1141,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                             ver.major,
                             ver.minor,
                             sym_plus_ver,
+                            size,
                         });
                     } else {
                         const sym_plus_ver = if (want_default)
@@ -1154,7 +1157,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                             \\.type {s}, %object;
                             \\.size {s}, {d};
                             \\.symver {s}, {s}{s}GLIBC_{d}.{d}.{d}
-                            \\{s}:
+                            \\{s}: .fill {d}, 1, 0
                             \\
                         , .{
                             sym_plus_ver,
@@ -1168,6 +1171,7 @@ pub fn buildSharedObjects(comp: *Compilation, prog_node: std.Progress.Node) !voi
                             ver.minor,
                             ver.patch,
                             sym_plus_ver,
+                            size,
                         });
                     }
                 }