[librm] Ensure that inline code symbols are unique

Commit 6149e0a ("[librm] Provide symbols for inline code placed into
other sections") may cause build failures due to duplicate label names
if the compiler chooses to duplicate inline assembly code.

Fix by using the "%=" special format string to include a
guaranteed-unique number within the label name.

The "%=" will be expanded only if constraints exist for the inline
assembly.  This fix therefore requires that all REAL_CODE() fragments
use a (possibly empty) constraint list.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/arch/x86/core/dumpregs.c b/src/arch/x86/core/dumpregs.c
index 37d62a7b6702fc1582f96331a178e1fa9d6842ad..a5108ea14db491152442f43a906b047fcc9af860 100644 (file)
--- a/src/arch/x86/core/dumpregs.c
+++ b/src/arch/x86/core/dumpregs.c
@@ -7,7 +7,7 @@ void __asmcall _dump_regs ( struct i386_all_regs *ix86 ) {
                TEXT16_CODE ( ".globl dump_regs\n\t"
                              "\ndump_regs:\n\t"
                              VIRT_CALL ( _dump_regs )
-                             "ret\n\t" ) );
+                             "ret\n\t" ) : );
 
        printf ( "EAX=%08x EBX=%08x ECX=%08x EDX=%08x\n"
                 "ESI=%08x EDI=%08x EBP=%08x ESP=%08x\n"

diff --git a/src/arch/x86/include/librm.h b/src/arch/x86/include/librm.h
index 6bad9c42b631bba6d86af2502ecebb9a00fa7f34..5196d390faff0ad24a0d8d6bce0e3caf9bc56f80 100644 (file)
--- a/src/arch/x86/include/librm.h
+++ b/src/arch/x86/include/librm.h
@@ -255,7 +255,7 @@ extern void remove_user_from_rm_stack ( userptr_t data, size_t size );
 #endif
 
 /* LINE_SYMBOL: declare a symbol for the current source code line */
-#define LINE_SYMBOL _S2 ( OBJECT ) "__line_" _S2 ( __LINE__ ) ":"
+#define LINE_SYMBOL _S2 ( OBJECT ) "__line_" _S2 ( __LINE__ ) "__%=:"
 
 /* TEXT16_CODE: declare a fragment of code that resides in .text16 */
 #define TEXT16_CODE( asm_code_str )                    \

diff --git a/src/arch/x86/interface/pcbios/bios_console.c b/src/arch/x86/interface/pcbios/bios_console.c
index 81e3a7d7e21aa6ae127b1c8db1761df252f52bb3..08fa6d036d9a1e056cc98933e399b6a29da961a1 100644 (file)
--- a/src/arch/x86/interface/pcbios/bios_console.c
+++ b/src/arch/x86/interface/pcbios/bios_console.c
@@ -521,12 +521,12 @@ static void bios_inject_startup ( void ) {
        __asm__ __volatile__ (
                TEXT16_CODE ( "\nint16_wrapper:\n\t"
                              "pushfw\n\t"
-                             "cmpb $0, %cs:bios_inject_lock\n\t"
+                             "cmpb $0, %%cs:bios_inject_lock\n\t"
                              "jnz 1f\n\t"
                              VIRT_CALL ( bios_inject )
                              "\n1:\n\t"
                              "popfw\n\t"
-                             "ljmp *%cs:int16_vector\n\t" ) );
+                             "ljmp *%%cs:int16_vector\n\t" ) : );
 
        /* Hook INT 16 */
        hook_bios_interrupt ( 0x16, ( ( intptr_t ) int16_wrapper ),

diff --git a/src/arch/x86/interface/pcbios/bios_reboot.c b/src/arch/x86/interface/pcbios/bios_reboot.c
index c6c5a5a914dee9bce46f561514514a1e3d6cd579..071173f1956e6b68d43737becf75d78e73ba959c 100644 (file)
--- a/src/arch/x86/interface/pcbios/bios_reboot.c
+++ b/src/arch/x86/interface/pcbios/bios_reboot.c
@@ -48,7 +48,7 @@ static void bios_reboot ( int warm ) {
        put_real ( flag, BDA_SEG, BDA_REBOOT );
 
        /* Jump to system reset vector */
-       __asm__ __volatile__ ( REAL_CODE ( "ljmp $0xf000, $0xfff0" ) );
+       __asm__ __volatile__ ( REAL_CODE ( "ljmp $0xf000, $0xfff0" ) : );
 }
 
 /**

diff --git a/src/arch/x86/interface/syslinux/comboot_call.c b/src/arch/x86/interface/syslinux/comboot_call.c
index 2f5c252c1147d053a15267aae90b6e3359b34884..e70f200e3324e51fd5377b417b4d2a6eb16c7963 100644 (file)
--- a/src/arch/x86/interface/syslinux/comboot_call.c
+++ b/src/arch/x86/interface/syslinux/comboot_call.c
@@ -663,7 +663,7 @@ void hook_comboot_interrupts ( ) {
                              VIRT_CALL ( int20 )
                              "clc\n\t"
                              "call patch_cf\n\t"
-                             "iret\n\t" ) );
+                             "iret\n\t" ) : );
 
        hook_bios_interrupt ( 0x20, ( intptr_t ) int20_wrapper, &int20_vector );
 
@@ -672,7 +672,7 @@ void hook_comboot_interrupts ( ) {
                              VIRT_CALL ( int21 )
                              "clc\n\t"
                              "call patch_cf\n\t"
-                             "iret\n\t" ) );
+                             "iret\n\t" ) : );
 
        hook_bios_interrupt ( 0x21, ( intptr_t ) int21_wrapper, &int21_vector );
 
@@ -681,7 +681,7 @@ void hook_comboot_interrupts ( ) {
                              VIRT_CALL ( int22 )
                              "clc\n\t"
                              "call patch_cf\n\t"
-                             "iret\n\t" ) );
+                             "iret\n\t" ) : );
 
        hook_bios_interrupt ( 0x22, ( intptr_t ) int22_wrapper, &int22_vector );
 }

diff --git a/src/arch/x86/transitions/librm_test.c b/src/arch/x86/transitions/librm_test.c
index ba4254fe40322ada62189433bd71bf9e69d9d2b3..77cf8022c48ac2ba4e10a2efb673ec7252960fd9 100644 (file)
--- a/src/arch/x86/transitions/librm_test.c
+++ b/src/arch/x86/transitions/librm_test.c
@@ -97,7 +97,7 @@ static void librm_test_exec ( void ) {
        /* Profile complete real-mode call cycle */
        for ( i = 0 ; i < PROFILE_COUNT ; i++ ) {
                profile_start ( &real_call_profiler );
-               __asm__ __volatile__ ( REAL_CODE ( "" ) );
+               __asm__ __volatile__ ( REAL_CODE ( "" ) : );
                profile_stop ( &real_call_profiler );
        }