When SECTION_RETAIN is used, issue a warning of symbol without used
attribute is placed in the same section with symbol with used attribute,
like
int __attribute__((used,section(".data.foo"))) foo2 = 2;
int __attribute__((section(".data.foo"))) foo1 = 1;
since assembler will put them in different sections with the same section
name.
gcc/
PR other/98121
* varasm.c (switch_to_section): Warn if symbol without used
attribute is placed in a section with symbol with used
attribute.
gcc/testsuite/
PR other/98121
* c-c++-common/attr-used-5.c: Updated.
* c-c++-common/attr-used-6.c: Likewise.
* c-c++-common/attr-used-7.c: Likewise.
* c-c++-common/attr-used-8.c: Likewise.
---
gcc/testsuite/c-c++-common/attr-used-5.c | 1 +
gcc/testsuite/c-c++-common/attr-used-6.c | 1 +
gcc/testsuite/c-c++-common/attr-used-7.c | 1 +
gcc/testsuite/c-c++-common/attr-used-8.c | 1 +
gcc/varasm.c | 19 +++++++++++++++++--
5 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/gcc/testsuite/c-c++-common/attr-used-5.c
b/gcc/testsuite/c-c++-common/attr-used-5.c
index 9fc0d3834e9..f9199587c51 100644
--- a/gcc/testsuite/c-c++-common/attr-used-5.c
+++ b/gcc/testsuite/c-c++-common/attr-used-5.c
@@ -10,6 +10,7 @@ extern struct dtv_slotinfo_list *list;
static int __attribute__ ((section ("__libc_freeres_fn")))
free_slotinfo (struct dtv_slotinfo_list **elemp)
+/* { dg-warning "without 'used' attribute is placed in a section with" "" {
target *-*-* } .-1 } */
{
if (!free_slotinfo (&(*elemp)->next))
return 0;
diff --git a/gcc/testsuite/c-c++-common/attr-used-6.c
b/gcc/testsuite/c-c++-common/attr-used-6.c
index 4526a692ee4..8f60c550be1 100644
--- a/gcc/testsuite/c-c++-common/attr-used-6.c
+++ b/gcc/testsuite/c-c++-common/attr-used-6.c
@@ -18,6 +18,7 @@ free_slotinfo (struct dtv_slotinfo_list **elemp)
__attribute__ ((section ("__libc_freeres_fn")))
void free_mem (void)
+/* { dg-warning "without 'used' attribute is placed in a section with" "" {
target *-*-* } .-1 } */
{
free_slotinfo (&list);
}
diff --git a/gcc/testsuite/c-c++-common/attr-used-7.c
b/gcc/testsuite/c-c++-common/attr-used-7.c
index fba2706ffc1..cca1f2b8a33 100644
--- a/gcc/testsuite/c-c++-common/attr-used-7.c
+++ b/gcc/testsuite/c-c++-common/attr-used-7.c
@@ -3,6 +3,7 @@
int __attribute__((used,section(".data.foo"))) foo2 = 2;
int __attribute__((section(".data.foo"))) foo1 = 1;
+/* { dg-warning "without 'used' attribute is placed in a section with" "" {
target *-*-* } .-1 } */
/* { dg-final { scan-assembler ".data.foo,\"aw\"" { target R_flag_in_section }
} } */
/* { dg-final { scan-assembler ".data.foo,\"awR\"" { target R_flag_in_section
} } } */
diff --git a/gcc/testsuite/c-c++-common/attr-used-8.c
b/gcc/testsuite/c-c++-common/attr-used-8.c
index c8d65f65033..c797610e1d7 100644
--- a/gcc/testsuite/c-c++-common/attr-used-8.c
+++ b/gcc/testsuite/c-c++-common/attr-used-8.c
@@ -2,6 +2,7 @@
/* { dg-options "-Wall -O2" } */
int __attribute__((section(".data.foo"))) foo1 = 1;
+/* { dg-warning "without 'used' attribute is placed in a section with" "" {
target *-*-* } .-1 } */
int __attribute__((used,section(".data.foo"))) foo2 = 2;
/* { dg-final { scan-assembler ".data.foo\n" { target R_flag_in_section } } }
*/
diff --git a/gcc/varasm.c b/gcc/varasm.c
index 7271705198c..fde00b5520e 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -7728,10 +7728,25 @@ switch_to_section (section *new_section, tree decl)
{
/* If the SECTION_RETAIN bit doesn't match, switch to a new
section. */
+ tree used_decl, no_used_decl;
+
if (DECL_PRESERVE_P (decl))
- new_section->common.flags |= SECTION_RETAIN;
+ {
+ new_section->common.flags |= SECTION_RETAIN;
+ used_decl = decl;
+ no_used_decl = new_section->named.decl;
+ }
else
- new_section->common.flags &= ~SECTION_RETAIN;
+ {
+ new_section->common.flags &= ~SECTION_RETAIN;
+ used_decl = new_section->named.decl;
+ no_used_decl = decl;
+ }
+ warning_at (DECL_SOURCE_LOCATION (no_used_decl),
+ OPT_Wattributes,
+ "%+qD without %<used%> attribute is placed in a "
+ "section with %qD with %<used%> attribute",
+ no_used_decl, used_decl);
}
else
return;
--
2.28.0
