GCN: Don't emit weak undefined symbols [PR119369]

This resolves all instances of PR119369
"GCN: weak undefined symbols -> execution test FAIL, 'HSA_STATUS_ERROR_VARIABLE_UNDEFINED'";
for all affected test cases, the execution test status progresses FAIL -> PASS.

This however also causes a small number of (expected) regressions, very similar
to GCC/nvptx:

    [-PASS:-]{+FAIL:+} g++.dg/abi/pure-virtual1.C  -std=c++17 (test for excess errors)
    [-PASS:-]{+FAIL:+} g++.dg/abi/pure-virtual1.C  -std=c++26 (test for excess errors)
    [-PASS:-]{+FAIL:+} g++.dg/abi/pure-virtual1.C  -std=c++98 (test for excess errors)

    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++11  scan-assembler .weak[ \t]*_?_ZTH11derived_obj
    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++11  scan-assembler .weak[ \t]*_?_ZTH13container_obj
    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++11  scan-assembler .weak[ \t]*_?_ZTH8base_obj
    PASS: g++.dg/cpp0x/pr84497.C  -std=c++11 (test for excess errors)
    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++17  scan-assembler .weak[ \t]*_?_ZTH11derived_obj
    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++17  scan-assembler .weak[ \t]*_?_ZTH13container_obj
    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++17  scan-assembler .weak[ \t]*_?_ZTH8base_obj
    PASS: g++.dg/cpp0x/pr84497.C  -std=c++17 (test for excess errors)
    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++26  scan-assembler .weak[ \t]*_?_ZTH11derived_obj
    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++26  scan-assembler .weak[ \t]*_?_ZTH13container_obj
    [-PASS:-]{+FAIL:+} g++.dg/cpp0x/pr84497.C  -std=c++26  scan-assembler .weak[ \t]*_?_ZTH8base_obj
    PASS: g++.dg/cpp0x/pr84497.C  -std=c++26 (test for excess errors)

    [-PASS:-]{+FAIL:+} g++.dg/ext/weak2.C  -std=gnu++17  scan-assembler weak[^ \t]*[ \t]_?_Z3foov
    PASS: g++.dg/ext/weak2.C  -std=gnu++17 (test for excess errors)
    [-PASS:-]{+FAIL:+} g++.dg/ext/weak2.C  -std=gnu++26  scan-assembler weak[^ \t]*[ \t]_?_Z3foov
    PASS: g++.dg/ext/weak2.C  -std=gnu++26 (test for excess errors)
    [-PASS:-]{+FAIL:+} g++.dg/ext/weak2.C  -std=gnu++98  scan-assembler weak[^ \t]*[ \t]_?_Z3foov
    PASS: g++.dg/ext/weak2.C  -std=gnu++98 (test for excess errors)

    [-PASS:-]{+FAIL:+} gcc.dg/attr-weakref-1.c (test for excess errors)
    [-FAIL:-]{+UNRESOLVED:+} gcc.dg/attr-weakref-1.c [-execution test-]{+compilation failed to produce executable+}

    @@ -131211,25 +131211,25 @@ PASS: gcc.dg/weak/weak-1.c scan-assembler weak[^ \t]*[ \t]_?c
    PASS: gcc.dg/weak/weak-1.c scan-assembler weak[^ \t]*[ \t]_?d
    PASS: gcc.dg/weak/weak-1.c scan-assembler weak[^ \t]*[ \t]_?e
    PASS: gcc.dg/weak/weak-1.c scan-assembler weak[^ \t]*[ \t]_?g
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-1.c scan-assembler weak[^ \t]*[ \t]_?j
    PASS: gcc.dg/weak/weak-1.c scan-assembler-not weak[^ \t]*[ \t]_?i

    PASS: gcc.dg/weak/weak-12.c (test for excess errors)
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-12.c scan-assembler weak[^ \t]*[ \t]_?foo

    PASS: gcc.dg/weak/weak-15.c (test for excess errors)
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-15.c scan-assembler weak[^ \t]*[ \t]_?a
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-15.c scan-assembler weak[^ \t]*[ \t]_?c
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-15.c scan-assembler weak[^ \t]*[ \t]_?d
    PASS: gcc.dg/weak/weak-15.c scan-assembler-not weak[^ \t]*[ \t]_?b

    PASS: gcc.dg/weak/weak-16.c (test for excess errors)
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-16.c scan-assembler weak[^ \t]*[ \t]_?kallsyms_token_index
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-16.c scan-assembler weak[^ \t]*[ \t]_?kallsyms_token_table
    PASS: gcc.dg/weak/weak-2.c (test for excess errors)
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-2.c scan-assembler weak[^ \t]*[ \t]_?ffoo1a
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-2.c scan-assembler weak[^ \t]*[ \t]_?ffoo1b
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-2.c scan-assembler weak[^ \t]*[ \t]_?ffoo1c
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-2.c scan-assembler weak[^ \t]*[ \t]_?ffoo1e
    PASS: gcc.dg/weak/weak-2.c scan-assembler-not weak[^ \t]*[ \t]_?ffoo1d

    PASS: gcc.dg/weak/weak-3.c  (test for warnings, line 58)
    PASS: gcc.dg/weak/weak-3.c  (test for warnings, line 73)
    PASS: gcc.dg/weak/weak-3.c (test for excess errors)
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-3.c scan-assembler weak[^ \t]*[ \t]_?ffoo1a
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-3.c scan-assembler weak[^ \t]*[ \t]_?ffoo1b
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-3.c scan-assembler weak[^ \t]*[ \t]_?ffoo1c
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-3.c scan-assembler weak[^ \t]*[ \t]_?ffoo1e
    PASS: gcc.dg/weak/weak-3.c scan-assembler weak[^ \t]*[ \t]_?ffoo1f
    PASS: gcc.dg/weak/weak-3.c scan-assembler weak[^ \t]*[ \t]_?ffoo1g
    PASS: gcc.dg/weak/weak-3.c scan-assembler-not weak[^ \t]*[ \t]_?ffoo1d

    PASS: gcc.dg/weak/weak-4.c (test for excess errors)
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1a
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1b
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1c
    PASS: gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1d
    PASS: gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1e
    PASS: gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1f
    @@ -131267,16 +131267,16 @@ PASS: gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1i
    PASS: gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1j
    PASS: gcc.dg/weak/weak-4.c scan-assembler weak[^ \t]*[ \t]_?vfoo1k

    PASS: gcc.dg/weak/weak-5.c (test for excess errors)
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1a
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1b
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1c
    PASS: gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1d
    PASS: gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1e
    PASS: gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1f
    PASS: gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1g
    PASS: gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1h
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1i
    [-PASS:-]{+FAIL:+} gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1j
    PASS: gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1k
    PASS: gcc.dg/weak/weak-5.c scan-assembler weak[^ \t]*[ \t]_?vfoo1l

These get 'dg-xfail-if'ed or 'dg-skip-if'ed, (mostly) similar to GCC/nvptx.

	PR target/119369
	gcc/
	* config/gcn/gcn-protos.h (gcn_asm_weaken_decl): Declare.
	* config/gcn/gcn.cc (gcn_asm_weaken_decl): New.
	* config/gcn/gcn-hsa.h (ASM_WEAKEN_DECL): '#define' to this.
	gcc/testsuite/
	* g++.dg/abi/pure-virtual1.C: 'dg-xfail-if' GCN.
	* g++.dg/cpp0x/pr84497.C: 'dg-skip-if' GCN.
	* g++.dg/ext/weak2.C: Likewise.
	* gcc.dg/attr-weakref-1.c: Likewise.
	* gcc.dg/weak/weak-1.c: Likewise.
	* gcc.dg/weak/weak-12.c: Likewise.
	* gcc.dg/weak/weak-15.c: Likewise.
	* gcc.dg/weak/weak-16.c: Likewise.
	* gcc.dg/weak/weak-2.c: Likewise.
	* gcc.dg/weak/weak-3.c: Likewise.
	* gcc.dg/weak/weak-4.c: Likewise.
	* gcc.dg/weak/weak-5.c: Likewise.

15 files changed, 32 insertions, 0 deletions

diff --git a/gcc/config/gcn/gcn-hsa.h b/gcc/config/gcn/gcn-hsa.h
index 658deac..6904aaa 100644
--- a/gcc/config/gcn/gcn-hsa.h
+++ b/gcc/config/gcn/gcn-hsa.h
@@ -46,6 +46,10 @@
 #define ASM_OUTPUT_LABEL(FILE,NAME) \
   do { assemble_name (FILE, NAME); fputs (":\n", FILE); } while (0)
 
+/* Used in lieu of '../elfos.h:ASM_WEAKEN_LABEL'.  */
+#define ASM_WEAKEN_DECL(STREAM, DECL, NAME, VALUE) \
+  gcn_asm_weaken_decl ((STREAM), (DECL), (NAME), (VALUE))
+
 #define ASM_OUTPUT_LABELREF(FILE, NAME) \
   asm_fprintf (FILE, "%U%s", default_strip_name_encoding (NAME))
 
diff --git a/gcc/config/gcn/gcn-protos.h b/gcc/config/gcn/gcn-protos.h
index 87d9092..1e513ba 100644
--- a/gcc/config/gcn/gcn-protos.h
+++ b/gcc/config/gcn/gcn-protos.h
@@ -18,6 +18,8 @@
 #define _GCN_PROTOS_
 
 extern void gcn_asm_output_symbol_ref (FILE *file, rtx x);
+extern void gcn_asm_weaken_decl (FILE *stream, tree decl, const char *name,
+				 const char *value);
 extern tree gcn_builtin_decl (unsigned code, bool initialize_p);
 extern bool gcn_can_split_p (machine_mode, rtx);
 extern bool gcn_constant64_p (rtx);
diff --git a/gcc/config/gcn/gcn.cc b/gcc/config/gcn/gcn.cc
index 48691c3..d59e87b 100644
--- a/gcc/config/gcn/gcn.cc
+++ b/gcc/config/gcn/gcn.cc
@@ -6927,6 +6927,20 @@ gcn_asm_output_symbol_ref (FILE *file, rtx x)
     }
 }
 
+void
+gcn_asm_weaken_decl (FILE *stream, tree decl, const char *name,
+		     const char *value)
+{
+  if (!value
+      && DECL_EXTERNAL (decl))
+    /* Don't emit weak undefined symbols; see PR119369.  */
+    return;
+  if (value)
+    ASM_OUTPUT_WEAK_ALIAS (stream, name, value);
+  else
+    ASM_WEAKEN_LABEL (stream, name);
+}
+
 /* Implement TARGET_CONSTANT_ALIGNMENT.
 
    Returns the alignment in bits of a constant that is being placed in memory.
diff --git a/gcc/testsuite/g++.dg/abi/pure-virtual1.C b/gcc/testsuite/g++.dg/abi/pure-virtual1.C
index ce7cd70..2df6133 100644
--- a/gcc/testsuite/g++.dg/abi/pure-virtual1.C
+++ b/gcc/testsuite/g++.dg/abi/pure-virtual1.C
@@ -4,6 +4,7 @@
 // { dg-additional-options "-fno-rtti -nostdlib++" }
 // { dg-additional-options "-Wl,-undefined,dynamic_lookup" { target *-*-darwin* } }
 // { dg-xfail-if "AIX weak" { powerpc-ibm-aix* } }
+// { dg-xfail-if PR119369 { amdgcn-*-* } }
 
 struct A
 {
diff --git a/gcc/testsuite/g++.dg/cpp0x/pr84497.C b/gcc/testsuite/g++.dg/cpp0x/pr84497.C
index be5a9d3..8a9478b 100644
--- a/gcc/testsuite/g++.dg/cpp0x/pr84497.C
+++ b/gcc/testsuite/g++.dg/cpp0x/pr84497.C
@@ -3,6 +3,7 @@
 // { dg-require-weak "" }
 // { dg-require-alias "" }
 // { dg-skip-if "No .weak" { { hppa*-*-hpux* } && { ! lp64 } } }
+// { dg-skip-if PR119369 { amdgcn-*-* } }
 
 struct Base
 {
diff --git a/gcc/testsuite/g++.dg/ext/weak2.C b/gcc/testsuite/g++.dg/ext/weak2.C
index 1bf2ddc..e1665cf 100644
--- a/gcc/testsuite/g++.dg/ext/weak2.C
+++ b/gcc/testsuite/g++.dg/ext/weak2.C
@@ -2,6 +2,7 @@
 // { dg-do compile }
 // { dg-require-weak "" }
 // { dg-options "" }
+// { dg-skip-if PR119369 { amdgcn-*-* } }
 
 // { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?_Z3foov" } }
 
diff --git a/gcc/testsuite/gcc.dg/attr-weakref-1.c b/gcc/testsuite/gcc.dg/attr-weakref-1.c
index f13aee4..1d25d9c 100644
--- a/gcc/testsuite/gcc.dg/attr-weakref-1.c
+++ b/gcc/testsuite/gcc.dg/attr-weakref-1.c
@@ -6,6 +6,7 @@
 // is not available on the following targets.  The test is skipped rather than
 // xfailed to suppress the warning that would otherwise arise.
 // { dg-skip-if "" { "hppa*-*-hpux*" "*-*-aix*" "nvptx-*-*" } }
+// { dg-skip-if PR119369 { amdgcn-*-* } }
 
 // For kernel modules and static RTPs, the loader treats undefined weak
 // symbols in the same way as undefined strong symbols.  The test
diff --git a/gcc/testsuite/gcc.dg/weak/weak-1.c b/gcc/testsuite/gcc.dg/weak/weak-1.c
index 6bbc669..9566ee0 100644
--- a/gcc/testsuite/gcc.dg/weak/weak-1.c
+++ b/gcc/testsuite/gcc.dg/weak/weak-1.c
@@ -4,6 +4,7 @@
 /* { dg-skip-if "" { *-*-mingw* } } */
 /* NVPTX's definition of weak looks different to normal.  */
 /* { dg-skip-if "" { nvptx-*-* } } */
+/* { dg-skip-if PR119369 { amdgcn-*-* } } */
 
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?a" } } */
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?b" } } */
diff --git a/gcc/testsuite/gcc.dg/weak/weak-12.c b/gcc/testsuite/gcc.dg/weak/weak-12.c
index d26fde6..fd18e59 100644
--- a/gcc/testsuite/gcc.dg/weak/weak-12.c
+++ b/gcc/testsuite/gcc.dg/weak/weak-12.c
@@ -4,6 +4,7 @@
 /* { dg-options "" } */
 /* NVPTX's weak is applied to the definition,  not declaration.  */
 /* { dg-skip-if "" { nvptx-*-* } } */
+/* { dg-skip-if PR119369 { amdgcn-*-* } } */
 
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?foo" } } */
 
diff --git a/gcc/testsuite/gcc.dg/weak/weak-15.c b/gcc/testsuite/gcc.dg/weak/weak-15.c
index 6364baf..425a700 100644
--- a/gcc/testsuite/gcc.dg/weak/weak-15.c
+++ b/gcc/testsuite/gcc.dg/weak/weak-15.c
@@ -4,6 +4,7 @@
 /* { dg-skip-if "" { x86_64-*-mingw* } } */
 /* NVPTX's weak is applied to the definition,  not declaration.  */
 /* { dg-skip-if "" { nvptx-*-* } } */
+/* { dg-skip-if PR119369 { amdgcn-*-* } } */
 
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?a" } } */
 /* { dg-final { scan-assembler-not "weak\[^ \t\]*\[ \t\]_?b" } } */
diff --git a/gcc/testsuite/gcc.dg/weak/weak-16.c b/gcc/testsuite/gcc.dg/weak/weak-16.c
index 2c58d65..44741c5 100644
--- a/gcc/testsuite/gcc.dg/weak/weak-16.c
+++ b/gcc/testsuite/gcc.dg/weak/weak-16.c
@@ -7,6 +7,7 @@
 /* { dg-skip-if "" { x86_64-*-mingw* } } */
 /* NVPTX's weak is applied to the definition,  not declaration.  */
 /* { dg-skip-if "" { nvptx-*-* } } */
+/* { dg-skip-if PR119369 { amdgcn-*-* } } */
 
 extern int kallsyms_token_index[] __attribute__((weak));
 extern int kallsyms_token_table[] __attribute__((weak));
diff --git a/gcc/testsuite/gcc.dg/weak/weak-2.c b/gcc/testsuite/gcc.dg/weak/weak-2.c
index 67171cf..f0f55f5 100644
--- a/gcc/testsuite/gcc.dg/weak/weak-2.c
+++ b/gcc/testsuite/gcc.dg/weak/weak-2.c
@@ -4,6 +4,7 @@
 /* { dg-skip-if "" { x86_64-*-mingw* } } */
 /* NVPTX's definition of weak looks different to normal.  */
 /* { dg-skip-if "" { nvptx-*-* } } */
+/* { dg-skip-if PR119369 { amdgcn-*-* } } */
 
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?ffoo1a" } } */
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?ffoo1b" } } */
diff --git a/gcc/testsuite/gcc.dg/weak/weak-3.c b/gcc/testsuite/gcc.dg/weak/weak-3.c
index 5fdf029..2046f1e 100644
--- a/gcc/testsuite/gcc.dg/weak/weak-3.c
+++ b/gcc/testsuite/gcc.dg/weak/weak-3.c
@@ -3,6 +3,7 @@
 /* { dg-require-weak "" } */
 /* { dg-options "-fno-common -Waddress" } */
 /* { dg-skip-if "" { x86_64-*-mingw* } } */
+/* { dg-skip-if PR119369 { amdgcn-*-* } } */
 
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?ffoo1a" } } */
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?ffoo1b" } } */
diff --git a/gcc/testsuite/gcc.dg/weak/weak-4.c b/gcc/testsuite/gcc.dg/weak/weak-4.c
index d0f3283..70e63d2 100644
--- a/gcc/testsuite/gcc.dg/weak/weak-4.c
+++ b/gcc/testsuite/gcc.dg/weak/weak-4.c
@@ -4,6 +4,7 @@
 /* { dg-skip-if "" { x86_64-*-mingw* } } */
 /* NVPTX's definition of weak looks different to normal.  */
 /* { dg-skip-if "" { nvptx-*-* } } */
+/* { dg-skip-if PR119369 { amdgcn-*-* } } */
 
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?vfoo1a" } } */
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?vfoo1b" } } */
diff --git a/gcc/testsuite/gcc.dg/weak/weak-5.c b/gcc/testsuite/gcc.dg/weak/weak-5.c
index 6f80bb0..3b23971 100644
--- a/gcc/testsuite/gcc.dg/weak/weak-5.c
+++ b/gcc/testsuite/gcc.dg/weak/weak-5.c
@@ -3,6 +3,7 @@
 /* { dg-require-alias "" } */
 /* { dg-options "-fno-common" } */
 /* { dg-skip-if "" { x86_64-*-mingw* } } */
+/* { dg-skip-if PR119369 { amdgcn-*-* } } */
 
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?vfoo1a" } } */
 /* { dg-final { scan-assembler "weak\[^ \t\]*\[ \t\]_?vfoo1b" } } */